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Daylight Saving Time, History, impacts, and

case study from Jordan

Hiba Abu-zaghleh

Jordan University of Science & Technology, Irbid, Jordan

A B S T R A C T

The principal reason for introducing (and extending) Daylight Saving Time (DST)

was, and still is, projected energy savings; particularly for electric lighting. This paper

presents the history of DST since the original idea until now, and a literature review

concerning the effects of DST on energy use and other effects.

In order to study the psychological impact of daylight saving time on people in

Jordan, a survey was conducted for this target, the main result was that there are

several impacts of DST switching on health, sleep, and related activities.

Introduction

Daylight Saving Time (DST) is a way of making better use of the natural daylight by

setting your clock forward one hour during the summer months, and back again in the

fall.

Many countries use DST to make better use of the natural daylight in the evenings,

and many don't. The difference in light is most noticeable in the areas close to the

Poles, e.g. furthest away from the Earth's equator.

1. Historical Background

Although DST has only been used for about 100 years, the idea was conceived many

years before. Ancient civilizations are known to have engaged in a practice similar to

modern DST where they would adjust their daily schedules to the Sun's schedule. For

example, the Roman water clocks used different scales for different months of the

Year.

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Benjamin Franklin

American inventor and politician Benjamin Franklin wrote an essay called “An

Economical Project for Diminishing the Cost of Light” to the editor of The Journal of

Paris in 1784. In the essay, he suggested, although jokingly, that Parisians could

economize candle usage by getting people out of bed earlier in the morning, making

use of the natural morning light instead.

Origin of the idea

At the age of 78, in a moment of whimsy, Benjamin Franklin wrote An Economical

Project, a discourse on the thrift of natural versus artificial lighting. He included

several funny regulations that Paris might adopt to help. Over two centuries later,

nations around the world use a variation of his concept to conserve energy and more

fully enjoy the benefits of daylight.

Franklin had eventually bedded down at three or four hours past midnight but was

awakened at six in the morning by a sudden noise. Surprised to find his room filled

with light, Franklin at first imagined that a number of the new oil lamps were the

source, but he soon perceived the light to be originating from the outside. Looking out

the window, Franklin saw the sun rising above the horizon, its rays pouring through

the open shutters. [3]

He wrote "I looked at my watch, which goes very well, and found that it was but six

o’clock; and still thinking it something extraordinary that the sun should rise so early,

I looked into the almanac, where I found it to be the hour given for his rising on that

day. I looked forward too, and found he was to rise still earlier every day towards the

end of June; and that no time during the year he retarded his rising so long as till eight

o clock. Your readers, who with me have never seen any sign of sunshine before

noon, and seldom regard the astronomical part of the almanac, will be as much

astonished as I was, when they hear of his rising so early; and especially when I

assure them, that he gives light as soon as he rises. I am convinced of this”

"This event has given rise in my mind to several serious and important reflections,"

the letter continued. Had he not been aroused at so early a morning hour, he would

have slept until noon through six hours of daylight and therefore, living six hours the

following night by candlelight. Realizing the latter was much more expensive than the

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former, he began calculating, for the sheer love of economy, the utility of his

discovery, the true test of any invention.

Benjamin Calculation

On the assumption that 100,000 Parisian families burned half a pound of candles per

hour for an average of seven hours per day (the average time for the summer months

between dusk and the supposed bedtime of Parisians), the account would stand thus:

"183 nights between 20 March and 20 September times 7 hours per night of candle

usage equals 1,281 hours for a half year of candle usage. Multiplying by 100,000

families gives 128,100,000 hours by candlelight. Each candle requires half a pound of

tallow and wax, thus a total of 64,050,000 pounds. At a price of thirty sols per pounds

of tallow and wax (two hundred sols make one livre tournois), the total sum comes to

96,075,000 livre tournois.”

"An immense sum," the astonished Franklin concluded, "that the city of Paris might

save every year."

Some "new" regulations

To answer skeptics who cried that old habits are hard to change, and it would be

difficult to induce the population of Paris to rise before noon, Franklin proposed the

following regulations:

1. A tax be laid on every window built with shutters to keep out the light of the sun.

2. Candles rationed to one pound per family per week, and the regulation enforced by

the constabulary.

3. Guards posted to stop the passage of all coaches, etc. upon the streets after sunset

except those of physicians, surgeons and midwives.

4. Every morning as soon as the sun shall rise, church bells and, if necessary, cannon

shall inform the citizenry of the advent of light and "awaken the sluggards effectually

and make them open their eyes to see their true interests ... All the difficulty will be in

the first two or three days; after which the reformation will be as natural and easy as

the present irregularity.... Oblige a man to rise at four in the morning, and it is

probable he will go willingly to bed at eight in the evening."

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Some of Franklin's friends, inventors of a new kind of oil lamp, were so taken by the

scheme that they continued corresponding with Franklin even after he returned to

America.

George Vernon Hudson

There's now broad agreement among historians that the true mastermind of daylight

saving time was George Vernon Hudson (1867-1946), a specialist in insect biology

(entomology) who left England for New Zealand in 1881. In 1895, when he first

presented the idea to the Royal Society of New Zealand, he was mocked. Other

members of the society deemed the proposal confusing and unnecessary. But attitudes

changed, and he lived to see his brainchild adopted by many nations including New

Zealand in 1927.

It all began because Hudson became frustrated because dusk came so early in summer

that it interfered with his evening bug-collecting rounds -- his day job was at the

Wellington Post Office. He figured the problem might be solved if the clock were

advanced two hours in summer and then shifted back in the winter, when he wasn't

bug-hunting anyway.

In a proposal in support of his idea, he explained that "The effect of this alteration

would be to advance all the day's operations in summer two hours compared with the

present system. In this way the early-morning daylight would be utilized, and a long

period of daylight leisure would be made available in the evening for cricket,

gardening, cycling, or any other outdoor pursuit desired."

When he presented his idea to the society, his peers acknowledged that it offered

some benefits but insisted that "calling the hours different would not make any

difference in the time. It was out of the question to think of altering a system that had

been in use for thousands of years, and found by experience to be the best."

Hudson followed up his proposal with an article in 1898, and although there was

interest in the idea, it was never followed through.

William Willett

In 1907, the Briton William Willett published a pamphlet entitled “The Waste of

Daylight”. In this document he proposed advancing clocks by 80 minutes in the

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summer. On successive Sundays in April, the clocks should be advanced by 20

minutes at 2 a.m., and be retarded by the same amount on Sundays in September. He

suggested that this would increase daylight recreation time, and save £2.5million on

energy for lighting.

Willett’s Daylight Saving plan caught the attention of Robert Pearce who introduced a

bill to the House of Commons in February 1908. The first Daylight Saving Bill was

drafted in 1909, presented to Parliament several times and examined by a select

committee. However, the idea was opposed by many, especially farmers, and thus the

bill was never made into a law. Willett died in 1915 without getting the chance to see

his idea come to life. [14]

DST first used

During World War I, Germany began observing DST, Clocks there were first turned

forward at 11:00 p.m. (23:00) on April 30, 1916. The rationale was to minimize the

use of artificial lighting in order to save fuel for the war effort during the war. The

idea was quickly followed by Britain and many other countries.

The US followed two years later, in 1918. After the war, all countries went back to

standard time until the outbreak of World War II. In that war, year-round DST

(abbreviated as YRDST) was instituted, and after the war many countries adopted

summer DST.

Year-round DST, also called “War Time”, was in force during World War II, from

February 9, 1942 to September 30, 1945. The change was implemented 40 days after

the bombing of Pearl Harbor.

Britain applied “Double Summer Time” during World War II by setting the clocks

two hours ahead of GMT during the summer and one hour ahead of GMT during the

winter.

After World War II

The American Congress enacted a trial period (1974-1975) of YRDST to save fuel

during the oil embargo. After the trial, the US returned to DST. Since then, DST in

the US has started on the first Sunday in April (or the last Sunday in March), and

ended on the last Sunday in October.

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The trial period showed that DST saved the energy equivalent of 10,000 barrels of oil

each day, but DST still proved to be controversial. Many complained that the dark

winter mornings endangered the lives of children going to school. After the energy

crisis was over in 1976, the U.S. changed their DST schedule again to begin on the

last Sunday in April. DST was amended again to begin on the first Sunday in April in

1987. Further changes were made after the introduction of the Energy Policy Act of

2005.

However, many European countries later abandoned daylight saving time, as DST

became a reminder of the war itself and the humiliation of foreign occupation. Both

the Italians and the French repealed DST after clearing up the debris of German

occupation. In fact, the French refused to adopt DST until the worldwide oil shortage

during the 1970s. Daylight saving time was instituted in France in 1975 following the

oil shock of 1974 with the aim to make savings by reducing lighting needs. This is

mainly to better match the operating hours with daylight hours to limit the use of

artificial lighting.

By the early 1980s, many countries of the European Union were using daylight saving

time, but they had different practices, thus impeding transport schedules and

communications within the continent. In 1996 the European Union (EU) standardized

an EU-wide daylight saving time for consistency to apply across the EU. Most

European countries that are EU-affiliated follow the EU rules or directives. The EU

daylight saving schedule runs from the last Sunday of March through the last Sunday

of October. [4]

DST in Jordan

Jordan start to use daylight saving time on June 6, 1973, in the followed years the

daylight saving schedule runs from the first of May and end on the first of October,

DST not observed between the years 1979-1984.

Jordan returned to the same schedule since 1985, but after the DST started in 2012 the

government planned to remain on DST, year-round for a second winter in a row this

decision had encountered fierce opposition from many Jordanians. The Jordanian

Teachers Association was particularly outspoken in their protest against the DST

schedule, which was first introduced in 2012. The JTA maintained that observing

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DST during the winter months puts students at risk who have to make their way to

school before sunrise.

On Friday, December 20, 2013 the Jordanian government has reversed its decision to

observe Daylight Saving Time all year. The current schedule for DST runs from the

last Friday of March through the last Friday of October.

2. Impact of DST

Saving energy

The rationale behind the 1975 study of DST-related energy savings was that energy

use and the demand for electricity for lighting homes is directly related to the times

when people go to bed at night and rise in the morning. In the average home, 25

percent of electricity was used for lighting and small appliances, such as TVs and

stereos. A good percentage of energy consumed by lighting and appliances occurred

in the evening when families were home. By moving the clock ahead one hour, the

amount of electricity consumed each day decreased.

In the summer, people who rose before the sun rises used more energy in the morning

than if DST were not in effect; this waste of energy from having less sunlight in the

morning was more than offset by the savings of energy that results from more sunlight

in the evening.

In the winter, the afternoon Daylight Saving Time advantage is offset for many people

and businesses by the morning's need for more lighting. In spring and fall, the

advantage is generally less than one hour. So, the rationale was that Daylight Saving

Time saves energy for lighting in all seasons of the year, but it saves least during the

four darkest months of winter (November, December, January, and February), when

the afternoon advantage is offset by the need for lighting because of late sunrise.

In addition, less electricity was thought to be used because people are home fewer

hours during the "longer" days of spring and summer. Most people plan outdoor

activities in the extra daylight hours. When people are not at home, they don't turn on

the appliances and lights.

Electricity use in residences comprised around 36% of total electricity use in the US

in 2005. Lighting makes up around 9% of all electricity use in US residences.

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Therefore, residential lighting is responsible for 3.5% of all electricity use in the US.

Metering and survey studies show that lights are switched on for an average of 2-3

hours per day in houses, and that most of this use occurs in the evening. Therefore, if

DST reduces this use by one hour for approximately half the year, total annual

electricity use would be reduced by approximately 0.7%. Of course, not all lighting is

used at night, and DST may increase the use of lighting during darker mornings, so a

final rough estimate of the total annual electricity reduction may be closer to 0.5%.

Lighting is used in many places other than residences, of course. But first-order

estimates suggest no substantial effect of DST for other lighting end uses.

Commercial and industrial buildings generally do not have lighting controls that

respond to external conditions, the lights are on at the same level for all working

hours. For street and other outdoor lighting, there are still the same number of hours

of darkness with or without DST, and therefore no change in energy use.

DST may also have an effect on the thermal energy use in buildings. For example,

with DST it will tend to be sunnier and warmer when people get home from work in

the summer, compared to the case with no DST. This may encourage increased use of

air conditioning, thus increasing electricity use. Similarly, it will be cooler and less

sunny in the early morning when people wake, which may increase the need for

heating energy, especially in spring and autumn months.

Similar effects will apply in commercial buildings, where there is a concern that the

increased air conditioning in the late afternoons may be coincident with system-wide

electricity demand peaks. However, building thermal effects are much more difficult

to estimate than direct lighting energy effects, and are highly dependent on the local

climate, and the characteristics of each building and its heating and cooling system.

There have been several studies over the past four decades to make more detailed

estimates of saving potential, or to demonstrate that savings actually occurred as a

result of DST transitions, some of these studies are being summarized in this paper.

A German study by Bouillon (1983) noted that total energy use in Europe doubled

from 1960 to 1983, while the proportion due to lighting decreased substantially, from

25% to 10%. This would tend to reduce the energy benefit of DST, if indeed the main

effect is on lighting use. [1]

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Ramos et al. (1998) referred to two theoretical studies to evaluate the saving potential

due to DST in Mexico. The studies estimated annual savings from 0.65% to 1.10% of

the total national use from reduced use of artificial lighting. The Mexican government

introduced DST in 1996 and, to assess the implementation, the energy use of 1996

was compared with 1995’s use. In 12 cities, 560 residential, 28 commercial, and 14

industrial customers were monitored. For the energy use of the residential customers,

the data were corrected for temperature, type of housing, and hour of the day during

the data analysis. Results showed that implementation of DST in 1996 brought overall

electrical use savings of 0.83%. These savings came exclusively from residential

buildings; no changes in use were detected for industrial and commercial customers.

The annual maximum demand was reduced by 2.6%. [8]

In New Zealand, an estimate by electricity market company M-Co in 2001 showed

that power usage decreased 3.5% in the first week after introducing daylight saving

time in 2000, with an average decrease of 2% over the previous 3 years. [10]

New studies have been initiated. Both Japan and Korea, which currently do not

implement DST, are exploring the consequences, with both countries anticipating

energy savings and economic stimulation. In 2004, the Sapporo Chamber of

Commerce and Industry launched a three-year pilot study on the Japanese island of

Hokkaido, with the goal of saving energy by reducing the use of electric lighting.

However, rather than resetting clocks, the employees of a sample of local

governments and commerce departments made an equivalent change in their work

schedules by starting work an hour earlier than usual during the Summer. First results

showed that two-thirds of the participants were positive about the national

introduction of DST. Opponents reported a lack of sleep and more overtime. The

South Korean Ministry of Commerce, Industry and Energy has initiated new research,

encouraged by a 1997 study by the Korea Energy Economics Institute that found that

“daylight saving time during the summer would reduce the home lighting electricity

use by 8.1% and electricity for air conditioning by 4.95%” [11]

Non-energy effects of DST

Some authors have discussed other DST effects in their reports. DST may affect

traffic safety, business, and leisure time, and may have physiological and

psychological effects.

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Shapiro et al. (1990) indicated that neither the change in photoperiod nor the effect of

a small change in circadian rhythm, both associated with DST, had an effect on the

psychiatric symptoms investigated e.g. suicide. [9]

Monk and Folkard (1976) used the DST time shift in the Fall of 1974 to study

adaptation to small time shifts and disruptions in behavior. The authors concluded that

waking time and associated alertness and body temperature were all affected, and that

adjustment to the time changes took several days. They speculated that the Spring

transition would be more disruptive, and indicated that preliminary data showed an

increase in road accidents. [6]

Several investigations have studied the effects of DST on traffic fatalities. With

regard to traffic fatalities in general, there are two possible relations between the

number of accidents and the clock shift. First, concentration is reduced due to a

disturbed circadian rhythm. Second, in general, pedestrians are more than twice as

likely to be killed in darkness as in daylight. The results of prior investigations differ

and are sometimes contradictory, which may be explained by differences in chosen

target group, or geographical location.

Lahti T. et al studied the amount of road traffic accidents one week before and one

week after transitions into and out of daylight saving time during years from 1981 to

2006. There results demonstrated that transitions into and out of daylight saving time

did not increase the number of traffic road accidents. [12]

Sood N. et al show that DST does save lives through reduced automobile crashes, and

does not impose any short term costs through a higher risk of crashes due to sleep

deprivation. [7]

Barnes et al (2009) used a National Institute for Occupational Safety and Health

database of mining injuries for the years 1983–2006, and they found that in

comparison with other days, on Mondays directly following the switch to Daylight

Saving Time -in which 1 hr is lost-workers sustain more workplace injuries and

injuries of greater severity. But on Mondays directly following the switch to Standard

Time -in which 1 hr is gained- there are no significant differences in sleep, injury

quantity, or injury severity. [2]

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There are few reports of the impact of DST on the circadian rhythms or daily rest-

activity cycles. Lahti T. et al study showed that Transition into daylight saving time

may have a disruptive effect on the rest-activity cycle in those healthy adults who are

short-sleepers or more of the evening type.

Transitions out of and into daylight saving time enhance night-time restlessness and

compromise the quality of sleep. They may thereby affect mood in a negative way

and be a concern for individuals with mood disorder in particular.

Transition to daylight saving time appears to compromise the process of sleep by

decreasing both sleep duration and sleep efficiency. [13]

Impact of DST in Jordan

A few studies have been made to analyze the DST energy saving in Jordan, Momani

M. et al study showed that the application of DST during the year 2000 saves the

electricity used for illumination by −0.73% but it increases the overall generation at

the onset and removal of DST by 0.5% and 1.4% due to increase in the heating and

cooling loads. The analysis showed that DST decreases the electricity demand at DST

onset by 0.2% and increases it at DST removal by 0.3%. A possible decrease in the

electricity consumption may take place if the DST is implemented from April to end

of August. [5]

Figure 1: Clock Time of Sunrise and Sunset in Jordan without DST

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Figure 2: Clock Time of Sunrise and Sunset in Jordan with DST

Figure 3: Number of Daylight hours In Jordan throughout the year

Figure 1 and 2 shows the time of sunrise and sunset in Jordan throughout the year

with and without DST, and figure 3 show the number of daylight hours each day in

the year.

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Daylight Saving Time Opinion Survey Results – A Case study from Jordan

In order to study the psychological impact of daylight saving time on people in

Jordan, a survey was conducted for this target, 263 participants filled out the survey

which contains 14 questions.

To get accurate results the age, sex, and employment status was taken into the

considerations, they had been asked a several questions which could be summarized

as follow:

- Do you support or oppose switching to Daylight Saving Time?

- Do the switch affect your mood status?

- Do the switch make you feel fatigued or sluggish?

- During the first period of the switch, do you suffer from headache?

- Does this switch disturb your biological clock?

- During the first period of the switch, does it affect your meal timing?

- How much time do you need for a readjustment?

- Do you have any idea about why the government makes this switch?

Main results and analysis

The survey results showed that 41% of participants support the switching to DST each

spring and back to the original time each fall, while 41% of them prefer to keep the

time throughout the year with the spring switching i.e. extended DST, the rest is

between they want the original time to be kept throughout the year, and they don’t

care.

48% of the participants said that their mood status change for the worst in the period

that close to the switching, while 20% report that their mood status change for the

better.

About feeling fatigued, the majority reported that there is such a thing. 73% of the

participants said there is no headache suffers during the first week of DST.

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About 80% showed that the switching affects their biological clock, either their

waking time or in adjusting going to sleep time.

The majority go with no effects when they had been asked about meal timing disturb

associated with the start and end of DST. About the time needed to readjust their days

41% said they need less than one week, while 42% need more than week, 7% said that

they couldn’t adapt with the switch.

Half of the participants know the reason for the DST switching and most of their

answers go with economics reason such as saving energy. Men and women in Jordan

are not different in their levels of switching to DST impacts. Opposition to switching

to DST increases significantly with age.

The majority of Jordanians are strongly opposed to switching to Daylight Saving time

each spring. There are several impacts of DST switching on health, sleep, and related

activities. No such a culture background about this switching which may enhance

people activity and performance so it could achieve its expected result.

3. Critique

The existing knowledge about how Daylight Saving Time affects energy use is

limited, incomplete, or contradictory. Many conclusions are the result of expectations

alone, are based on constrained assumptions, or are older than 25 years.

Economical, geographical, and climatological factors have major effects on electricity

end use. Studies should always correct for such factors.

Energy use and human behavioral patterns have changed substantially since the first

introduction of DST. These are likely to have a major influence on the effect of DST

on energy use.

Even if overall energy use is unchanged by DST, hourly energy use is changed,

affecting electricity demand profiles. Effects of DST on lighting energy use are

mainly noticeable in residential buildings.

So energy-wise, i opine that DST is essentially pointless, an opinion I’ll stick to until i

see the results of a broader study (which will no doubt have to be inordinately

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complex and probably befuddling to most of us). Most of the world’s population does

not observe it in any way and we live in an ever more globalized society.

But for now, the only reason I can see to hold on to the DST model is convenience

and luxury. Even in standard time, few of us actually rise with the sun in summertime.

Most peoples’ routines have been structured around the eight-to-five workday, so

even if the sun rose at 5 a.m., the majority would probably sleep until it’s time to get

ready for work. So, just as Benjamin Franklin, George Vernon Hudson and William

Willet suggested at least a century ago, having that extra hour of daylight to frolic,

relax, take a walk or just get outside under the bright summer sun.

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References

1. Bouillon, H., 1983, Mikro- und Makroanalyse der Auswirkungen der

Sommerzeit auf den Energie-Leistungsbedarf in den verschiedenen

Energieverbrauchssektoren der Bundesrepublik Deutschland, IFR

Schriftenreihe 13, Dissertation TU München (in German).

2. Christopher M. Barnes and David T. Wagner, 2009, Changing to Daylight

Saving Time Cuts into Sleep and Increases Workplace Injuries, Journal of

Applied Psychology, Vol. 94, No. 5, 1305–1317

3. Franklin, B., 1784, Essay on Daylight Saving, Letter to the Editor of the

Journal of Paris. In: Nathan G. Goodman (Ed.), The Ingenious Dr. Franklin,

Selected Scientific Letters, University of Pennsylvania Press, 1931, pp. 17-22.

4. Gurevitz, M., 2005, Daylight Saving Time, CRS Report for Congress, Order

code RS22284. Available online at

http://fpc.state.gov/documents/organization/55726.pdf.

5. Momania. M, Yatima. B, Mohd Alia. M, 2009, The impact of the daylight

saving time on electricity consumption—A case study from Jordan, Energy

Policy, Volume 37, Issue 5, May 2009, Pages 2042–2051

6. Monk, T.H., Folkard, S., 1976, Adjusting to the changes to and from Daylight

Saving Time, Nature 261, 688-689

7. Neeraj Sood and Arkadipta Ghosh (2007) “The Short and Long Run Effects of

Daylight Saving Time on Fatal Automobile Crashes,” The B.E. Journal of

Economic Analysis & Policy: Vol. 7: Iss. 1 (Contributions), Article 11.

8. Ramos, G.N., Covarrubias, R.R., Sada, J.G., Buitron, H.S., Vargas, E.N.,

Rodriguez, R.C., 1998, Energy saving due to the implementation of the

daylight saving time in Mexico in 1996, Proceedings International Conference

on Large High Voltage Electric Systems, CIGRE'98, Paris, France, vol. 13, 6

pp.

9. Shapiro, C.M., Blake, F., Fossy, E., Adams, B., 1990, Daylight saving time in

psychiatric illness, Journal of Affective Disorders 19, pp. 177-181.

10. Small, V., 2001, Daylight saving idea to beat cuts, The New Zealand Herald.

Available online at

http://www.nzherald.co.nz/topic/story.cfm?c_id=187&objectid=207726,

published online 15 August 2001.

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11. South African Press Association (Sapa), 2005, Thousands embark on daylight

savings campaign, Independent Online

12. Tuuli A. Lahti, Sami Leppamaki, Jouko Lonnqvist, Timo Partonen, 2006,

Transition to daylight saving time reduces sleep duration plus sleep efficiency

of the deprived sleep, Neuroscience Letters 406, pp. 174–177

13. Tuuli A. Lahti, Sami Leppamaki, Jouko Lonnqvist, Timo Partonen, 2008,

Transitions into and out of daylight saving time compromise sleep and the

rest-activity cycles, BioMed Central

14. Willett, W., 1907, Pamphlet, Sloane Square, London. In: Essay reprinted in

British Time by Donald de Carle, Crosby Lockwood & Son Ltd, London,

1946, pp. 152-157.

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APPENDIX

Survey results

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