effect of charging for carrier bags on bin-bag sales in wales

Final Report

Effect of charging for carrier bags

on bin-bag sales in Wales

This report contains analysis of the impact of the carrier-bag charge introduced in Wales in 2011 on the sales of bin bags. It quantifies the increase in sales and compares this increase to the reduction in carrier-bag use that accompanied the introduction of the charge. There is also information on trends in sales of bags for life during this period.

Project code: Internal project ISBN: 978-1-84405-461-9 Research date: June – September 2013 Date: December 2013

WRAP’s vision is a world without waste, where resources are used sustainably. We work with businesses, individuals and communities to help them reap the benefits of reducing waste, developing sustainable products and using resources in an efficient way. Find out more at www.wrap.org.uk Document reference: [e.g. WRAP, 2006, Report Name (WRAP Project TYR009-19. Report prepared by…..Banbury, WRAP]

Written by: Tom Quested (WRAP)

Front cover photography: An assortment of carrier bags, packed inside each other

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Effect of charging for carrier bags on bin-bag sales in Wales

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Executive summary

In October 2011, a five-pence charge was introduced in Wales for ‘single-use’ carrier bags (which includes ‘thin-gauge’ carrier bags)1. This led to a dramatic reduction in the number of this type of carrier bag supplied – for instance, grocery retailers experienced a reduction of 81% between 2010 and 2012. There is limited evidence from other countries that such a reduction in the use of carrier bags leads to an increase in the sale of bin liners: this study explores this potential effect in Wales. This study has found that the introduction of this charge led to a small increase in sales of some types of bin bag and this increase persisted for at least one-and-a-half years (to the end of the measurement period). The increase was only seen in swing-bin and pedal-bin liners (the latter is shown as an example in Figure ES1); no increase was seen for refuse sacks or nappy sacks.

Figure ES1: Number of pedal-bin liners sold, indexed: 100 = four weeks to 12th June 2010

This finding suggests that some people in Wales were using thin-gauge carrier bags as bin liners, and that the introduction of a carrier-bag charge was responsible for an increase in the purchases of swing-bin and pedal-bin liners. It also suggests that thin-gauge carrier bags were only used as a substitute – at a level that could be detected in this analysis – for similar sized bin bags. The analysis employed in this study allowed the increase in bin-bag sales to be quantified by both number and weight of bags. Over 2012, the sales of swing-bin and pedal-bin liners in the whole retailer market were estimated at 11 million higher than if the charge had not been introduced, equating to 80 tonnes of material. These increases were small in comparison to the reduction of thin-gauge carrier bags associated with the charge’s introduction. For the seven largest grocery retailers, there was a reduction of 284 million thin-gauge carrier bags (2,129 tonnes) between 2010 and 2012. Therefore, the increase in bin-liner sales was around 4% of the reduction in thin-gauge

1 See glossary for more details of definitions.


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carrier bags (by weight or number; Figure ES2). If other changes in thin-gauge carrier bag usage were also included (i.e. those associated with the c. 20% of the grocery market not covered by the seven retailers and other (non-grocery) sectors), the uplift in bin-bag sales would have been smaller in comparison than suggested by the figures above. The relatively small magnitude of the increased sales of bin bags suggests that the majority of thin-gauge carrier bags were not being used as bin liners; had this been the case, the increase in bin-bag sales would have been on a similar scale to the reduction in thin-gauge carrier bags.

Figure ES2: Representation of changes in weight of bags used in Wales between 2010 and 2012

* Data for seven grocery retailers providing carrier-bag information to WRAP, covering 82% of grocery market. † Five retailers were also able to provide bag-for-life data for Wales. Data on thin-gauge carrier bags and bags for

life for these retailers is presented.

The study also quantified the increased use of bags for life around the time of the introduction of the charge. For the five grocery retailers that were able to supply Welsh-specific data on bags for life and thin-gauge carrier bags, the increase in material used for bags for life (463 tonnes) was 28% of the reduction in thin-gauge carrier bags (1,654 tonnes; Figure ES2). This means that there was a net positive change associated with material use, but smaller in magnitude than if only changes associated with thin-gauge carrier bags were considered. Therefore, it is recommended that any assessment of the impact of the carrier-bag charge in Wales takes into account the increases in bags-for-life use and bin-bag sales. The information provided in this report could be used to inform such an assessment. The results from this study are specific to Wales: the magnitude of the unintended effects of a carrier-bag charge are likely to depend on factors including the details of the legislation (e.g. which bags are covered) and the proportion of the population using carrier bags as bin liners.

1,654 tonnes less material (thin-gauge carrier bags for 5 grocery retailers†)

463 tonnes more material (bags for life for 5 grocery retailers†)

80 tonnes more material (bin bags; whole retail market)

2,129 tonnes less material (thin-gauge carrier bags for 7 grocery retailers*)


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Contents

1.0 Introduction ................................................................................................. 6 2.0 Data sources and analysis methods .............................................................. 7

2.1 Bin-bag sales data ...................................................................................... 7 2.2 Analysis details .......................................................................................... 8 2.3 Bin-bag weight data ................................................................................... 9

3.0 Results ........................................................................................................ 10 3.1 Trends over time: Wales & West and Great Britain ...................................... 10 3.2 Counterfactual analysis ............................................................................. 12 3.3 Discussion of results of counterfactual analysis ........................................... 15 3.4 Comparison of changes relating to the carrier-bag charge ........................... 16

3.4.1 Thin-gauge carrier bags .................................................................. 16 3.4.2 Bags for life ................................................................................... 17 3.4.3 Bin-bags ........................................................................................ 18 3.4.4 Comparison of changes .................................................................. 18

4.0 Summary and conclusions .......................................................................... 21 Appendix 1: Nielsen ScanTrack data .................................................................... 22

Glossary

Single-use carrier bag – the Welsh Government introduced a charge on this type of bag in 2011 and the associated legislation carried a definition, which included stipulations on material, size of the bag and gauge (thickness) of material used2. As defined by this legislation, ‘single-use carrier bag’ is a broader category than ‘thin-gauge carrier bag’ (see below), although thin-gauge carrier bags account for a large proportion of all single-use carrier bags used.

Thin-gauge carrier bag – in this report, thin-gauge carrier bags are defined as either those made from polyethylene and less than 25 microns in gauge, or made from paper (any gauge); this is consistent with WRAP’s reporting of carrier-bags use within the grocery sector. Given the good coverage of data provided by grocery retailers to WRAP on thin-gauge carrier bags, this information is used as comparator to bin-bag sales within this study. For this reason, much of the report refers to trends in thin-gauge carrier bags use as a result of legislation in Wales.

Bag for life – in this report, all carrier bags not defined as thin-gauge are defined as bags for life. These are sometimes referred to as reusable bags.

Acknowledgements

WRAP are grateful to Nielsen for the provision of sales data on bin bags.

2 http://www.legislation.gov.uk/wsi/2010/2880/regulation/3/made

http://www.legislation.gov.uk/wsi/2010/2880/regulation/3/made


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1.0 Introduction In October 2011, a charge was introduced in Wales for ‘single-use’ carrier bags (which includes thin-gauge carrier bags)3. This meant that this type of bag could no longer be given away for free by retailers when goods were purchased, and retailers had to charge a minimum of 5 pence; the Welsh Government encouraged this money to be donated to good causes4. This led to a dramatic reduction in thin-gauge carrier bags, as documented by the Welsh Government5 and WRAP6. It also triggered an increase in the use of reusable bags7. However, one potential consequence of a charge of this nature is an increase in sales of bin bags, e.g. refuse sacks or pedal-bin liners. The suggestion is that, as some of the population use thin-gauge carrier bags as bin liners, the reduction in the number of thin-gauge carrier bags taken from retailers leads to an increase in the number of bin bags purchased. For instance, following the introduction of a charge in the Republic of Ireland in 2002, a 77% increase in the sales of ‘kitchen tidy bags’ (bin-liners) was reported8. Similarly, the introduction of a carrier-bag ban (rather than a charge) in South Australia led to the proportion of the population buying bin liners increasing from 15% to 80%9. This study explores whether there is evidence of an increase in sales of bin bags in Wales around October 2011. Sales data were obtained for relevant types of bin bags (§2.1) and a comparison was made between Wales and the rest of Great Britain, as described in §2.2. As detailed in the results (Chapter 3.0), the analysis was able to identify different sales patterns in Wales around the time of the charge’s introduction. This allowed the magnitude of the effects associated with the carrier-bag charge to be compared for thin-gauge carrier bags, ‘bags for life’10 and bin bags.

3 In this study, the term ‘thin-gauge carrier bag’ is mainly used (unless referring to the Welsh Government’s charge specifically), as the analysis is investigating the extent to which the bags are used again for containing waste: i.e. the analysis is looking at the extent to which these thin-gauge carrier bags are used multiple times. See glossary for more details.

4 More details of the charge, including the regulations can be found at the following link: http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/?lang=en

5 http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/reduction/?lang=en

6 UK Voluntary Carrier Bag Monitoring – 2013 (WRAP, 2013): http://www.wrap.org.uk/sites/files/wrap/Carrier%20bags%20results%20%282012%20data%29.pdf

7 Consumer behavioural study on the use and re-use of carrier bags 2012 (Welsh Government and Zero Waste Scotland, 2013): http://wales.gov.uk/docs/desh/publications/130903behaviour-study-on-carrier-bags-report-en.pdf

8 As reported by Environment Australia in Plastic Shopping Bags – Analysis of Levies and Environmental Impacts – Final Report http://www.environment.gov.au/archive/settlements/publications/waste/plastic-bags/pubs/analysis.pdf

9 Review of the Plastic Shopping Bags (Waste Avoidance) Act 2008 (Martin Aspin, 2012): http://www.zerowaste.sa.gov.au/upload/resource-centre/publications/plastic-bag-phase-out/PBActReview_maspin_Nov2012_2%20-%20final.pdf

10 In this study, bags for life are those not categorised as thin gauge.

http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/?lang=en

http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/reduction/?lang=en

http://www.wrap.org.uk/sites/files/wrap/Carrier%20bags%20results%20%282012%20data%29.pdf

http://wales.gov.uk/docs/desh/publications/130903behaviour-study-on-carrier-bags-report-en.pdf

http://www.environment.gov.au/archive/settlements/publications/waste/plastic-bags/pubs/analysis.pdf

http://www.zerowaste.sa.gov.au/upload/resource-centre/publications/plastic-bag-phase-out/PBActReview_maspin_Nov2012_2%20-%20final.pdf

http://www.zerowaste.sa.gov.au/upload/resource-centre/publications/plastic-bag-phase-out/PBActReview_maspin_Nov2012_2%20-%20final.pdf


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2.0 Data sources and analysis methods 2.1 Bin-bag sales data The data for the sales of bin-bags in the UK was supplied by Nielsen from their ScanTrack data. Nielsen ScanTrack is obtained from Electronic Point of Sale (EPoS) data and covers the following market breakdowns:

Grocery multiples

Multiple forecourts

Multiple off licences

Convenience multiples

Symbol groups

Independents

See Appendix 1 for more details of the ScanTrack data. Information was supplied for the category of ‘bin and waste bags’, which is subdivided into the following types of bags:

Refuse

Nappy sacks

Swing bin

Pedal bin

Garden refuse

Compost bag

Dust bin

Wheelie bin

Rubble sack

Vanity bags

Storage bags

Other

The information was supplied using three metrics: value of sales, number of bags, and number of packs sold (e.g. a roll of 40 bags would be counted as one ‘pack’, but 40 bags). Most of the analysis in this report focuses on the number of bags. The information was supplied as totals for four-week periods, from the four-week period ending 12th June 2010 to that ending 8th June 2013. The geographical areas supplied were: England & Wales, Scotland, Northern Ireland, and ‘Wales & West’. This latter category is based on TV viewing areas. Assessment by WRAP of the postcodes covered by this region suggested that it includes around 2.7 million people in Wales (around 90% of the total population of Wales) and around 2.3 million people in England (specifically in Somerset, Wiltshire and the Bristol area). Given that bag sales in Wales are a specific focus of this study, this geographic classification was not ideal. However, it was not cost-effective for WRAP to obtain Wales-only data. Furthermore, the methods used for analysing the data were able to identify changes in sales within Wales from the Wales & West data, as described in the next section. To give a scale of bin-bag usage in the UK, the number and value of bin bags is presented in Table 1 for the final year for which data were provided (52 weeks from 10th June 2012 to 8th June 2013). The total number of bags used in this period, 3.44 billion, represents around 54 bags per person per year, at a cost of £3.


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Table 1: Number and value of bin bag sales in the UK (52 weeks from 10th June 2012 to 8th June 2013), split by main bag types

Bag type Number of

bags (millions) Value of sales (£ millions)

Refuse 1,422 £114

Swing bin 497 £25

Pedal bin 471 £16

Nappy sacks 830 £6

Other 220 £31

Total 3,440 £191

Source: Nielsen ScanTrack

There are some sources of bin bags not covered by the Nielsen ScanTrack data (e.g. some local authorities providing refuse sacks to their residents). It has not been possible to obtain data on the provision of these bags, but they are likely to represent a small number of bags compared to those covered by the ScanTrack data. 2.2 Analysis details Comparisons were made for each of the major types of bag in turn, namely: refuse, swing bin, pedal bin, and nappy sacks. These four categories cover the vast majority of bin and waste bags, representing 93% of this category by number of bags and 87% by weight. The main analysis compared information for ‘Wales & West’ with the remainder of Great Britain. Data for the remainder of Great Britain was obtained by subtracting data for Wales & West from that for Great Britain. The comparison used the information for the remainder of Great Britain to construct a counterfactual for Wales & West: the number of bags that would have been sold in Wales & West if sales had changed in proportion to those in the rest of Great Britain.

Information for Northern Ireland was not used for the counterfactual because a charge was

introduced for carrier bags towards the end of the analysis period (April 2013), rendering the

data for Northern Ireland unsuitable for constructing a counterfactual that represented no

charging for carrier bags.

By using this method, the difference between the actual sales for Wales & West and the

counterfactual described above could be ascribed to the following:

Any change in the levels of sales in Wales (due to the charge or otherwise);

Any change in the levels of sales in the West of England covered by Wales & West, which

would include some of the geographical ‘spill-overs’ effects from the charge (if there are

any). An example of such a geographical spill over would be people from Wales shopping

over the border in England in order to obtain free carrier bags. Given the short distances

that most people travel for the majority of shop trips (and those to obtain bin bags in

particular), it is likely that these spill-over effects are small in magnitude. This analysis

would not pick up any spill-over effects that occurred in England near the Welsh border

that are not covered by the Wales & West area.


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If bin-bag sales were similar in the English part of Wales & West to the rest of Great Britain,

the difference in sales is attributable to changes in Wales. Given the data presented in

Chapter 3.0, this appears to be a valid assumption.

The main part of the analysis was undertaken using information on the number of bags. Some of the key results were converted into weights towards the end of the analysis using the average weights found in §2.3. 2.3 Bin-bag weight data Weights for each type of bag were obtained for previous (unpublished) research by WRAP. A sample of bags were purchased and weighed from a number of supermarkets in February 2009. The mean weight for each type of bag was calculated from the sample. This provided an approximate figure for the weight of each bag type (Table 2). By multiplying the number of bags sold by the average weight of an individual bag from that category, the total weight of bags sold was estimated.

Table 2: Average weight of individual bags for the most common bag types

Bag type Bag weight,

mean (g) Number of products

sampled

Refuse 25.1 11

Swing bin 10.7 6

Pedal bin 5.9 5

Nappy sacks 1.2 7


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3.0 Results 3.1 Trends over time: Wales & West and Great Britain Before presenting the results from the counterfactual analysis, this section provides information on the sales of bags in Wales & West compared to those in the whole of Great Britain. Information is presented for the four most-sold types of bags: refuse, swing-bin, pedal-bin and nappy sacks. The sales data are indexed to the first period (the four weeks to the 12th June 2010) for ease of comparison. Figure 1 compares sales of refuse bags between Wales & West and Great Britain. There was no differential effect around the time that the charge was introduced (October 2011). However, there appeared to be a decline in the number of refuse sacks purchased in Wales & West compared to the Great Britain over this period: by June 2013, the end of the 3-year period for which data were acquired, the sales in Wales were around 6% lower. This could be connected to the faster increase in recycling rates in Wales, reducing the need for residual waste containment; however, further investigation of this phenomenon would be required to determine if this was a substantial contributory factor; this is beyond the scope of this study.

Figure 1: Number of refuse bags sold, indexed: 100 = four weeks to 12th June 2010

Source: Nielsen ScanTrack: 3 x 52 weeks to 8th June 2013

The same data are presented for nappy sacks in Figure 2. Similar to refuse sacks, there appeared to be no differential effect of any substantial magnitude between Wales & West and Great Britain, either at the time the charge was introduced or at any other point during the 3-year period.


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Figure 2: Number of nappy sacks sold, indexed: 100 = four weeks to 12th June 2010


For swing-bin liners, there was an increase in sales in Wales & West compared to Great Britain after the introduction of the charge (Figure 3). In particular, there was a marked increase in the 4-week period ending 29th October 2011 that was sustained to at least June 2013, the last period for which sales data were obtained. The magnitude of this uplift has been calculated in the counterfactual analysis (§3.2).

Figure 3: Number of swing-bin liners sold, indexed: 100 = four weeks to 12th June 2010



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There was also an uplift in sales for pedal-bin liners directly after the introduction of the carrier-bag charge (Figure 4). Again, this uplift was sustained until at least June 2013. The uplift for pedal-bin liners was proportionately greater than that for swing-bin liners.

Figure 4: Number of pedal-bin liners sold, indexed: 100 = four weeks to 12th June 2010


The analysis in this section suggests that the carrier-bag charge had minimal impact on sales of refuse bags and nappy bags. In contrast, sales of pedal-bin liners and swing-bin liners increased as the charge was introduced. As discussed in §3.3, these results suggest that thin-gauge carrier bags were frequently being used as a substitute for similar-sized waste bags (pedal- and swing-bin liners) prior to the introduction of the carrier-bag charge, but not for smaller nappy bags or larger refuse bags. The next section contains analysis to quantify the changes for the two bag types where a change was seen using a counterfactual analysis.

3.2 Counterfactual analysis This section presents results of the comparisons between ‘Wales & West’ and the rest of Great Britain, as detailed in §2.2. This analysis was only performed for the two types of bag that showed a differential effect around the time of the carrier-bag charge’s introduction, i.e. pedal- and swing-bin liners. As detailed in the section on analysis details (§2.2), the counterfactual is the level of sales in Wales & West if they had tracked those in the rest of Great Britain. Given the discussion in §3.3, the difference between the actual level of sales and the counterfactual following the introduction of the carrier-bag charge is a quantitative estimate of the effect of the charge on bin-bag sales.


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Figure 5 shows this analysis for swing-bin liners. For the first 4 weeks after the charge (four weeks ending 29th October 2011), the sales were 340,000 bags higher than the counterfactual, having been almost the same (c. 10,000 lower) in the previous four weeks. An uplift in sales was sustained for the rest of the analysis period, varying between 170,000 and 370,000 bags more than the counterfactual. These results are also expressed as the difference between the actual and counterfactual in Figure 6.

Figure 5: Swing-bin liners sold in Wales & West from June 2010 to June 2013, compared to counterfactual


Figure 6: Difference between actual sales of swing-bin liners and counterfactual in Wales & West from June 2010 to June 2013



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A similar effect occurs for pedal-bin liners (Figure 7): for the four-week period ending on 1st October 2011 (i.e. just before the introduction of the charge) sales of pedal bin liners were 200,000 bags higher than the counterfactual. Sales then rose to just over 4 million for the period ending 29th October, approximately 1 million bags higher than the counterfactual.

Figure 7: Pedal-bin liners sold in Wales & West from June 2010 to June 2013, compared to counterfactual


The actual level of sales maintained an uplift over the counterfactual, although the magnitude of the uplift reduced to an average of around 600,000 bags (for a four week period) from the beginning of 2012 to the end of the analysis period (June 2013).

Figure 8: Difference between actual sales of pedal-bin liners and counterfactual in Wales & West from June 2010 to June 2013



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3.3 Discussion of results of counterfactual analysis The results in §3.2 show a change in the sales of pedal- and swing-bin liners at the time of the introduction of the carrier-bag charge. This change is in the form of a structural break – an immediate uplift that is then sustained for the rest of the analysis period. This appears to give clear evidence of an effect on bin-bag sales from the carrier-bag charge. Drawing this conclusion from the analysis makes three assumptions:

The effect seen is not due to ‘scatter’ in the data, either due to measurement issues or other differences between Wales & West and the rest of Great Britain;

The changes seen are in Wales, rather than the English part of Wales & West; and

Other changes did not occur in Wales around the time of the charge’s introduction. For the first point, in the period prior to the introduction of the carrier-bag charge (i.e. from June 2010 to September 2011), the actual and counterfactual differ by a maximum of 250,000 bags (a 9% difference) for any four-week period. The average magnitude of difference between the actual and counterfactual is 120,000 bags. (The differences seen prior to the charge introduction are similar in magnitude for pedal-bin liners and swing-bin liners.) These differences could be due to differences in the way bin bags (or carrier bags) are sold or distributed between Wales and the rest of Great Britain or scatter in the data due to the nature of sales measurement. However, the key point is that the average ‘scatter’ in the data (c. 120,000 bags) is considerably smaller than the changes seen at the point of introduction: for pedal-bin liners, there was an immediate increase of 800,000 bags, which plateaued at an uplift of around 600,000 bags. For swing-bin liners, the immediate increase was 340,000 bags, settling at an average of 250,000 bags for the remainder of the period. It is therefore highly unlikely that the change seen in October 2011 is a result of the scatter seen in the data: both the sharp increase at the exact moment of the carrier-bag charge introduction and the sustained increase in bin-bag sales point to an effect caused by the charge’s introduction. Furthermore, there is a logical mechanism for the increase: people reducing the number of carrier bags used as bin liners due to fewer thin-gauge carrier bags in circulation. We do not have data to validate or invalidate the second assumption but the timings of the changes suggest that it would be unlikely that the observed effect was driven by changes in the English part of Wales & West, given that the change in Wales & West is seen in October 2011 (i.e. exactly as the charge was introduced), whilst no similar increase was seen in the rest of Great Britain. As stated in §2.2, this counterfactual analysis would include geographical spill-over effects of the charge that occurred in the English part of Wales & West, namely people from Wales buying more bin bags in the parts of Somerset, Wiltshire and the Bristol area covered by the Wales & West area. However, it omits any spill-over effects occurring in other parts of England. The exact magnitude of spill-over effects is not known, but it would seem likely that they are relatively small – most people travel only short distances to buy bin bags and only a small proportion of the Welsh population live close to the border with England. For the third point, there may have been changes to the way retailers sold bin bags in response to the charge’s introduction (e.g. changes to pricing and promotions). If these did occur, these could still be attributable to the introduction of the charge, although the mechanism of action would have been different (i.e. mediated by a change by retailers). The fact that the uplift in sales persisted for at least one-and-a-half years (i.e. longer than most


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promotional offers) suggests that this mechanism is likely to have had a minor contribution on the observed uplift. The conclusion of the above is that, although information was provided for the geographical entity of Wales & West, the analysis method used allowed the differential effect in Wales to be teased out. Therefore, this study provides evidence that there was an effect on bin-bag sales from introducing a carrier-bag charge in Wales. In the next section, comparison is made between the magnitude of this unintended effect and changes in carrier-bag usage in Wales around the time of the charge’s introduction.

3.4 Comparison of changes relating to the carrier-bag charge This section compares the effect of various changes in bag usage that occurred in Wales around the time of the introduction of the carrier-bag charge in October 2011. Specifically, a quantitative comparison is made between the sale and distribution of the following:

Thin-gauge carrier bags (see glossary for definition)

Bags for life (reusable bags)

Bin-bag types showing an effect related to the carrier-bag charge: i.e. pedal-bin and

swing-bin liners

This comparison is made by comparing estimates of the change in bag use due to the carrier-bag charge, as they manifested themselves in 2012, i.e. after transient effects of the first three months had reduced. For thin-gauge carrier bags and bags for life, this is done by comparing the last full year of data before the charge (2010) with the first full year after the charge (2012). For bin bags, the comparison is made between actual sales in 2012 and the counterfactual, based on the sales in the rest of Great Britain. 3.4.1 Thin-gauge carrier bags Two sources of data were available for thin-gauge carrier bags or single-use carrier bags:

Information published by the Welsh Government covering a range of sectors provided to

Welsh Government by the British Retail Consortium, directly from retailers, and sourced

from the internet11; and

Data relating to seven grocery retailers (supermarkets), as reported by WRAP12.

Comparison in this study was made using data published by WRAP, as this provides quantitative information on the change in carrier-bag use in Wales by number and weight of bags. However, this information focuses on the grocery sector. Although it would have been useful to include as many sectors as possible in these comparisons, the information published by the Welsh Government does not present changes in the number or weight of bags. Information published by Welsh Government is provided as percentage reductions and this means that it is difficult to compare it to data on bin-bag sales. The WRAP data also contains estimates of sales of bags for life in Wales for five of the seven supermarkets. (The other two retailers do not provide WRAP with a split of bags for life sales by the nations of the UK.) Of the sales of bags for life in the UK, these five supermarkets

11 http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/reduction/?lang=en

12 Data for Asda, Co-operative Group, Marks & Spencer, Morrison’s, Sainsbury’s Supermarkets Ltd, Tesco and Waitrose; these supermarkets cover around 82% of the grocery sector by volume: http://www.wrap.org.uk/sites/files/wrap/Carrier%20bags%20results%20%282012%20data%29.pdf

http://wales.gov.uk/topics/environmentcountryside/epq/waste_recycling/substance/carrierbags/reduction/?lang=en

http://www.wrap.org.uk/sites/files/wrap/Carrier%20bags%20results%20%282012%20data%29.pdf


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cover more than 90% of the seven that report to WRAP. Despite these limitations, the comparison presented below allows the increase in bin-bag sales to be put into context. Following the introduction of the carrier-bag charge in Wales, the number of thin-gauge carrier bags supplied by the seven retailers supplying data to WRAP fell by 81%, from 351 million in 2010 to 66 million in 2012 (Table 3). Similarly, the weight of these bags reduced by 81% over the same time period: from 2,618 tonnes to 489 tonnes. A similar trend was also seen for the five retailers that also supplied Welsh-specific data on bags for life13.

Table 3: Changes in weight and weight of thin-gauge carrier bags in Wales between 2010 and 2012

2010 2011 2012 Change 2010 - 2012

All seven retailers:

Number (millions) 351 273 66 –284 (–81%)

Weight (tonnes) 2,618 2,103 489 –2,129 (–81%)

Five retailers that report Welsh-specific data on bags for life:

Number (millions) 268 205 47 –221 (–82%)

Weight (tonnes) 1,994 1,577 337 –1,654 (–83%)

Thin-gauge carrier bags are defined as polyethylene bags of a gauge (thickness) of less than 25 microns, and

paper bags (all gauges)

3.4.2 Bags for life At the same time that the number of thin-gauge carrier bags fell, the number of bags for life increased. Data for the five retailers able to supply information for Wales is shown in Table 4. This shows an increase of 15.7 million bags between 2010 and 2012, from 12.1 million to 27.8 million: i.e. bag numbers more than doubled14.

Table 4: Changes in weight and weight of bags for life in Wales between 2010 and 2012

2010 2011 2012 Change 2010 - 2012

Five retailers that report Welsh-specific data on bags for life:

Number (millions) 12.1 19.0 27.8 +15.7 (+130%)

Weight (tonnes) 384 653 847 +463 (+121%)

13 To maintain the anonymity of data for individual retailers (part of the terms associated with the supply of data to WRAP), the names of these five retailers are not provided in this study.

14 The change in provision of bags (both thin-gauge and bags for life) between 2010 and 2012 in Wales has been assumed to be attributable to the carrier bag charge. It would be possible to construct a counterfactual based on the rest of the UK, but this would have a minor effect on the results as changes in carrier bag usage in the UK were small in comparison to those in Wales. For instance, the number of bags for life sold in the UK for the seven retailers increased by 0.4% between 2010 and 2012.


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3.4.3 Bin-bags Data for pedal-bin and swing-bin liners has been determined by taking the difference between the actual level of sales and the counterfactual. The time period used was the 52 weeks running from 25th December 2011 to 22nd December 2012: i.e. that most closely corresponding to the calendar year 2012. As discussed in §2.2 and §3.3, although this data is for Wales & West, the increase quoted is likely to be a good estimate for the change in Wales.

Table 5: Uplift in actual sales of bin-bag liners in Wales & West during 2012 compared to counterfactual

Number of bags (millions) Weight (tonnes)

Swing-bin liners 3.1 33

Pedal-bin liners 8.0 47

Total 11.1 80

3.4.4 Comparison of changes The changes in carrier-bag usage in Wales between 2010 and 2012 are compared to the uplift in bin-bag sales due to the carrier-bag charge during 2012 in Table 6. This shows that the increase in bin-bag sales was small in magnitude compared to the reduction in thin-gauge carrier bags, whether assessed by number or weight. The changes in Table 6 are illustrated graphically in Figure 9 and Figure 10.

Table 6: Summary of changes in number and weight of bags in Wales between 2010 and 2012

Change 2010 to 2012

Number of bags (million) Weight (tonnes)

Thin-gauge carrier bags (7 retailers) –284 –2,129

Thin-gauge carrier bags (5 retailers)a –221 –1,654

Bags for life (same 5 retailers)a +15.7 +463

Bin bagsb +11.1 +80

a For comparative purposes, the thin-gauge carrier bags estimates are given for the five retailers that were also

able to give bag-for-life data for Wales b This is the difference between actual sales and the counterfactual during 2012, rather than the change between

2010 and 2012; data presented for pedal-bin and swing-bin liners only


19

Figure 9: Representation of changes in number of bags used in Wales between 2010 and 2012




Figure 10: Representation of changes in weight of bags used in Wales between 2010 and 2012




The uplift in bin-bag sales was around 4% (by number or weight) of the reduction in thin-gauge carrier bags for the seven grocery retailers. If other changes in thin-gauge-bag usage were also included (i.e. those associated with the c. 20% of the grocery market not covered

284 million fewer thin-gauge carrier bags (for 7 grocery retailers)

221 million fewer thin-gauge carrier bags (for 5 grocery retailers)a

15.7 million more bags for life (for 5 grocery retailers)a

11.1 million more bin bags (whole retail market)b

1,654 tonnes less material (thin-gauge carrier bags for 5 grocery retailers)a

463 tonnes more material (bags for life for 5 grocery retailers)a

80 tonnes more material (bin bags; whole retail market)b

2,129 tonnes less material (thin-gauge carrier bags for 7 grocery retailers)


20

by the seven retailers and other (non-grocery) sectors), the uplift in bin-bag sales would have been comparatively smaller than suggested by this percentage. The comparison also shows that the increase in number of bags for life was small (15.7 million) when compared to the reduction in thin-gauge carrier bags for the 5 retailers with Welsh-specific data (221 million): i.e. around 7% of the reduction in thin-gauge carrier bags. However, the increase in bags for life was more substantial when assessed by weight. The increase of 463 tonnes was 28% of the reduction in thin-gauge carrier bags for the five retailers (1,654 tonnes): i.e. between a quarter and a third of the reduction in material use associated with thin-gauge carrier bags was negated by the increase in bags for life.


21

4.0 Summary and conclusions This study has found that the introduction of a charge on thin-gauge carrier bags in Wales was associated with an increase in bin-bags sales. In particular, increases in sales over and above those expected had no charge been introduced (given trends in the rest of Great Britain) were seen in swing-bin and pedal-bin liners around October 2011. These increases persisted at least to the end of the measurement period (June 2013). This finding suggests that people in Wales were using thin-gauge carrier bags as bin liners15, and that the introduction of a carrier-bag charge was responsible for an increase in the purchases of swing-bin and pedal-bin liners. It also suggests that thin-gauge carrier bags were only used as a substitute – at a level that could be detected in this analysis – for similar sized bin bags. There was no evidence of an increase in sales of (much larger) refuse bags or (smaller) nappy bags around the time of the charge’s introduction. The analysis employed in this study allowed the increase in bag sales to be quantified by both number and weight of bags. Over 2012, the sales of swing-bin and pedal bin liners were estimated at 11 million higher than if the charge had not been introduced, equating to 80 tonnes of material. These increases were small in comparison to the reduction of thin-gauge carrier bags associated with the charge’s introduction. Compared to the reduction between 2010 and 2012 in thin-gauge carrier bags from seven grocery retailers regularly supplying data to WRAP for monitoring purposes, the increase in bin-bag sales was around 4% (by weight or number). The relatively small magnitude of the bin-bag uplift suggests that the majority of thin-gauge carrier bags were not being used as bin liners; had this been the case, the increase in bin-bag sales would have been on a similar scale to the reduction in thin-gauge carrier bags. The increase in the amount of material used for bin bags was sufficient to offset only a small amount of the reduction associated with thin-gauge carrier bags as a result of the charge. However, the increased use of bags for life around the time of the introduction of the charge was associated with a larger increase in material use. For the five grocery retailers that were able to supply Welsh-specific data for both thin-gauge carrier bags and bags for life, the increase in material used for bags for life was 28% of the reduction in thin-gauge carrier bags. This means that there was a net positive change associated with bag use (for these retailers), but considering only trends in thin-gauge carrier bags would lead to an overestimation of the benefits of a charge. Therefore, it is recommended that assessment of the impact of the carrier-bag charge in Wales takes into account the increase in bags-for-life use (alongside the increase in bin-bag sales)16. The results from this study are specific to Wales: the magnitude of unintended effects of a carrier bag charge would depend on factors including the details of the legislation (e.g. which bags are covered) and the proportion of the population using carrier bags as bin liners.

15 Consistent with other studies, such as: Consumer behavioural study on the use and re-use of carrier bags 2012 (Welsh Government and Zero Waste Scotland, 2013): http://wales.gov.uk/docs/desh/publications/130903behaviour-study-on-carrier-bags-report-en.pdf

16 The information provided in this report is not intended as an impact assessment for the carrier-bag charge in Wales, but the information in this report could be used to inform such an assessment.




22

Appendix 1: Nielsen ScanTrack data This appendix includes details of the Nielsen ScanTrack universe. The table on the next page lists the retailers (split by trade channel) that were included in the data provided to WRAP. The trade channels are defined as follows:

Grocery multiples: Defined list of retailer coverage. A grocer belonging to a group of 10 or

more retail shops operated under common ownership.

Co-ops: A Co-op is any store owned by any co-operative society and trading under any

co-operative society fascia, (except Co-op Chemists).

Multiple forecourts: Stores that make up this trade channel provide a read of Company

Owned Company Operated Forecourts (CoCos) and Company Owned Dealer Operated

Forecourts (CoDos).

Multiple off licences: An off licence is an outlet authorised to sell alcoholic drink for

consumption off the premises only, excluding those limited to sales of medicinal wines

and those where the major business is wholesale cash & carry. Multiple off licences are

those where a group with 10 or more branches are operated under common ownership

and fascia.

Convenience multiples: Defined list of retailer coverage. A convenience store belonging to

a group of 10 or more shops operated under common ownership.

Symbol groups: Includes both fee-paying and non-fee paying organisations of

independent retailers who buy supplies through a specific wholesaler, which are then

delivered direct to the shop (definition aligned with the IGD).

Independents: Single enterprises with less than 10 outlets under common ownership.

The following terms are used in the table on the next page:

Census: data received from all stores for these retailers.

Sample: data received from a sample of stores for these retailers, and these are used to

represent other stores in the universe. Note that in most cases, the sample is not

designed to represent the specific retailer that the stores are from.

Universe: data not received from these retailers. Data from retailers that do supply

Nielsen is expanded to represent these retailers as a group within each trade channel.

Estimated: data not received from these retailers. They are estimated using data from the

retailers Nielsen receive, but the estimate is specifically tailored to represent these

retailers individually.


23

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http://www.wrap.org.uk/content/carrier-bags



effect of charging for carrier bags on bin-bag sales in wales

Documents