understanding activity patterns and trends david levinson
TRANSCRIPT
Understanding Activity Patterns and Trends
David Levinson
Introduction
• Travel and Activity are Two Sides of the Same Coin
• Time in Travel is inseparable from Time at Activity
• Activities Considered (Home, Work, Shop, Other)
• Daily Activity Budget (24 hrs)
Space-Time Prism
Chances
Time-Axis
X-Axis8:00 am Home
Y-Axis
8:20 am
2:20 pm
1:20 pm
5:10 pm
4:45 pm
5:15 pm
5:20 pm
1:30 pm
2:10 pm
Store
Lunch
Work
2001 NHTS: Trips By Purpose
Washington DC Metropolitan Area1968 to 1988
0
20
40
60
80
100
120
140
Capacity Population Households Autos VMT
Percentage Change
Montgomery County Trends
Patterns
Type # Tour type Coding1 Simple work H-W-H2 Simple maintenance H-M-H3 Simple discretionary H-D-H4 Complex work only H-W-W-…-H5 Complex maintenance only or
Complex discretionary onlyH-M-M-…-HH-D-D-…-H
6 Complex work + maintenance only H-W-M-…-H*7 Complex work + discretionary only H-W-D-…-H*8 Complex maintenance + discretionary only H-M-D-…-H*9 Complex work + maintenance +
DiscretionaryH-W-M-D-H*
*tripmaking could take place in any order
Information Networks
• Fundamental question … how do we choose non-work destinations?
• First time (acquire information)• Repeats (experience, habit)• Choose between known and
unknown destinations.
Where does Information Come From
• Formal: media networks: TV, Radio, Internet, Yellow Pages
• Informal: social networks
Changes in RetailStores By Type
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
1990 1992 1994 1996 1998 2000 2002 2004
Year
Number of Stores
Chain Drug StoreIndependent Drug StoreMass MerchandiserSupermarket
Economies of Scale in Supermarkets
Median Grocery Store Size
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
1990 1992 1994 1996 1998 2000 2002 2004
Year
Square Feet
Questions
• Is congestion rising?• Are commutes getting longer?• Are people spending more time
commuting?• Are people spending more time traveling?• How do the declining trip times and
increasing speeds reconcile with the general perception of worsening congestion?
More Questions
• What do travel and activity depend on?
• Is spatial determinism correct?• Does income matter?• Does location matter?• Does demographics matter?
Rational Locator Hypothesis
• Despite falling speeds and increasing distances, average travel time can remain constant.
• Individuals will adjust their home and work locations in order to maintain commuting durations in the face of rising congestion.
• Dispersion and decentralization are conscious choices that enable rational locators to achieve their goals.
Rational Allocator Hypothesis
• Changes in Time Allocation (1968 to 1988) due to rising female labor force participation.
• Can be understood in context of Bounded Rationality
• “Allocators” - shape temporal activity patterns within household, spending time and money to produce household goods, maximizing utility.
• Technology, rising per capita income, and labor force participation create substition of in-house activities by out-of-home activities. E.g. eating out, day care.
Activity Duration Calculation
DC Time Use Data
Work outside
homeNon-workers
Activity Year Male Female Male Female
Home 1968 786 831 1120 1225
1988 799 826 1143 1165
1994 761 795 1093 1155
Work 1968 515 487 0 0
1988 472 447 0 0
1994 499 476 0 0
Work-related 1968 0 0 0 0
1988 0 0 0 0
1994 20 10 0 0
Shop 1968 7 10 27 52
1988 10 13 31 50
1994 8 13 33 47
Other 1968 44 29 217 101
1988 61 62 187 140
1994 47 47 220 154
Travel 1968 88 82 76 62
1988 99 92 80 85
1994 104 99 93 85
Twin Cities
Time Use Data
Workers Non-workers
Activity Year Male Female Male Female
Home 1990 777 816 1092 1176
2000 777 802 1044 1122
Work 1990 485 466 0 0
2000 494 476 0 0
Work-related 1990 29 11 83 14
2000 14 9 96 33
Shop 1990 7 15 21 41
2000 8 14 26 36
Other 1990 53 55 144 131
2000 56 56 168 161
Travel 1990 88 77 101 78
2000 90 84 106 87
* Denotes Significance at 95% level
SEX_YEAR WORK STATUS TRAVEL CASESHOME WORK SHOP OTHER
Female1995 Non Worker 1172* 0 42* 166* 60 28121990 1220 0 35 127 58 10201995 Worker 944 313* 25* 93* 65 80141990 928 284 30 132 65 2535Male1995 Non Worker 1171* 0 30 177* 62 12401990 1222 0 29 130 59 3611995 Worker 900 365* 15* 90* 70 77161990 903 338 20 110 69 2275
TIME SPENT AT
Comparison of 1990 and 1995 NPTS
Change in Person Work Trip Volume (AM Peak
Period)DESTINATIO
N:CENTER CITY INNER SUBURBS OUTER SUBURBS TOTAL
ORIGIN ‘68 ‘88 ‘68 ‘88 ‘68 ‘88 ‘68 ‘88
CENTER CITY
235 252 7 32 31 -3 14 25 76 282 308 9
INNER SUBURBS
122 126 3 58 91 56 30 57 93 210 274 30
OUTER SUBURBS
86 192 124 41 106 160 74 342 365 200 641 220
TOTAL 443 569 28 131 229 74 118 425 261 692 1223 77
Change in Average Work Trip Time (AM Peak
Period)DESTINATION
CENTER CITY INNER SUBURBS OUTER SUBURBS REGIONAL AVERAGE
ORIGIN ‘68 ‘88 ‘68 ‘88 ‘68 ‘88 ‘68 ‘88
CENTER CITY
31.2 30.5 -2.2 36.3 28.9 -21.0 45.3 36.0 -20.5 32.3 30.5 -5.3
INNER SUBURBS
37.3 35.0 -6.2 20.4 22.8 11.8 27.0 32.3 19.6 31.1 30.4 -2.3
OUTER SUBURBS
45.2 47.7 5.5 29.4 38.3 30.3 20.6 25.6 24.3 33.0 34.3 3.9
Drive Alone Trip Distribution
Trip Distances and Speeds
• Increased for Work Trips by All Modes (6.5 to 7.8 (> 20%) miles Euclidean (multiply by 1.4 or so to get Network Distances))
• Distances increased slightly for nonwork trips (< 10% for home based, about 25% for other to other )
• Speeds up in general (~20% for work trips).
Resolving the Paradox
Suburban Arterial
Urban Radial
1968 Speed 55 MPH 25 MPH
1988 Speed 40 MPH 20 MPH
1968 Traffic 10% 90%
1988 Traffic 50% 50%
Weighted Averages
• While Speed drops on both facilities, Average Speed rises from 28 MPH to 30 MPH.
• More generally, speed can drop on every facility from the day it opens as traffic increases, but if people increasingly use higher speed facilities, that use will outweigh the speed drop.
• This may be of little comfort to the commuter whose work trip becomes worse every year until he relocates.
Trip Chaining
• As available time shrinks, trip chaining is a practical substitute.
• Rather than – home to work to home to other to
home.
• We see– home to work to other to home.
Trip Peaking: Work Trips
Trip Peaking: Nonwork Trips
Travel and Activity Patterns
1990 vs. 1995 NPTS• Time Spent at Home Decreased for Non
Workers and Female Workers• Time at Home in 1990 Substituted for
Work in 1995, especially for Female Workers
• Time Spent at Other Declined for Workers but Increased for Non-Workers
• Overall Travel Times have either remained Stable or Increased, but not significant
Travel Duration• Travel Duration = f( Activity Duration &
Frequency)• TDi = ß0 + ß1 * ADi + ß2 * AFi• Transport Planning Models Only Consider
Activity Frequency, not Duration• ADi positive & significant in 6 of 9
activity categories, negative & significant for 1 of 9 (home) [ Staying Home is Substitute for Travel ]
Correlations: Activity Complements or
Substitutes• Non-Travel Activities are Substitutes• Travel is Complementary to Like Activity
& Travel to Home; Substitutes for Other Activities.
Matrix TotalCells
Positive and Significant
Negative andSignificant
Activity-Activity 66 1 29
Activity-Travel 144 15 39
Travel-Travel 66 11 10
Conclusions• Activity Duration a key factor
explaining travel duration• Activities are substitutes• Travel is complement only to like
activity & return trip• Activity Duration is fairly constant
between groups, with large individual variations which are not easily predicted
Residential Density vs. Time Use
0
200
400
600
800
1000
1200
0-99 100-249250-499500-749750-9991000-19992000-29993000-39994000-49995000-74997500-1000010000-4999950000
+
Residential Density (ppsm)
Time (home,
work)
02040
6080100120
140160
Time (shop, other, travel)
HOME WORK SHOP OTHER TRAVEL
HOME WORK SHOP OTHER TRAVELCMSA Name 1990 Population Mean Std Dev t-stat Mean Std Dev t-stat Mean Std Dev t-stat Mean Std Dev t-stat Mean Std Dev t-stat Cases
Hartford, CT 1.1 998 249 0.90 243 266 -1.06 23 60 0.37 108 151 0.41 67 66 -0.44 301Providence, RI 1.1 1055 238 1.62 181 256 -1.68 20 38 -0.37 134 142 1.13 50 35 -2.90 30Buffalo, NY 1.2 1045 323 0.92 241 297 -0.30 20 31 -0.41 62 118 -1.77 72 114 0.13 24Portland, OR 1.5 1012 261 0.72 242 287 -0.44 17 50 -0.67 102 146 -0.12 67 54 -0.20 49Milwaukee, WI 1.6 975 253 -0.25 334 265 1.84 21 40 -0.15 56 107 -2.93 53 34 -2.99 43Cincinnati, OH 1.7 974 261 -0.31 265 297 0.14 34 80 1.24 99 131 -0.32 67 56 -0.30 67Denver, CO 1.8 973 266 -0.47 287 290 0.97 24 51 0.42 94 146 -0.76 63 43 -1.47 112Pittsburgh,PA 2.2 1054 239 2.67 203 257 -2.02 28 59 0.99 94 129 -0.74 60 44 -1.83 86Seattle, WA 2.6 965 261 -0.73 258 256 -0.07 18 56 -0.75 118 190 0.67 82 88 1.40 98Cleveland, OH 2.8 953 257 -1.16 254 271 -0.21 20 51 -0.39 120 156 0.93 93 141 1.64 91Miami, FL 3.2 1009 251 0.90 204 258 -2.03 33 72 1.48 131 146 1.72 63 49 -1.18 90Houston, TX 3.7 981 252 -0.16 243 265 -0.71 20 48 -0.52 132 169 1.87 64 47 -1.28 134Dallas, TX 3.9 1001 263 0.71 264 276 0.19 20 41 -0.63 91 123 -1.24 64 63 -0.88 130Boston, MA 4.2 966 255 -0.78 271 276 0.41 11 23 -4.74 115 154 0.70 78 67 1.37 113Detroit, MI 4.7 960 254 -1.18 281 271 0.96 21 59 -0.16 112 150 0.57 66 49 -0.73 156Philadelphia, PA 5.9 988 260 0.16 260 264 0.02 25 59 0.60 98 142 -0.69 70 63 0.24 198San Francisco, CA 6.3 1026 271 2.17 214 257 -2.49 19 41 -0.92 112 165 0.61 68 69 -0.11 210Chicago, IL 8.1 993 269 0.52 263 271 0.18 25 67 0.71 96 155 -0.95 64 58 -1.49 299Los Angeles, CA 14.5 962 255 -1.84 279 276 1.47 22 58 0.09 110 156 0.75 66 57 -1.01 501New York, NY 18.1 979 256 -0.61 267 273 0.80 21 53 -0.43 100 157 -0.92 72 67 1.55 1237
985 258 260 272 22 55 105 154 69 66 3969
Census Division vs. Activity Duration
0%
20%
40%
60%
80%
100%
New England Middle Atlantic East NorthCentral
West NorthCentral
South Atlantic East SouthCentral
West SouthCentral
Mountain Pacific
Census Division
Proportion of Day at Activity
HOME WORK OTHER TRAVEL SHOP
Time at Home by Income Level
0
200
400
600
800
1000
1200
1400
Less Than$5,000$5,000-$9,999$10,000-$14,999$15,000-$19,999$20,000-$24,999$25,000-$29,999$30,000-$34,999$35,000-$39,999$40,000-$44,999$45,000-$49,999$50,000-$54,999$55,000-$59,999$60,000-$64,999$65,000-$69,999$70,000-$79,999$75,000-$79,999$80,000
+
Income Level
Time (in minutes)
Female, Non-Worker Female, Worker Male, Non-Worker Male, Worker
Time at Work by Income Level
0
50
100
150
200
250
300
350
400
Less Than$5,000$5,000-$9,999$10,000-$14,999$15,000-$19,999$20,000-$24,999$25,000-$29,999$30,000-$34,999$35,000-$39,999$40,000-$44,999$45,000-$49,999$50,000-$54,999$55,000-$59,999$60,000-$64,999$65,000-$69,999$70,000-$79,999$75,000-$79,999$80,000
+
Income Level
Time (in minutes)
Female, Worker Male, Worker
Time at Shop by Income Level
0
10
20
30
40
50
60
Less Than$5,000$5,000-$9,999$10,000-$14,999$15,000-$19,999$20,000-$24,999$25,000-$29,999$30,000-$34,999$35,000-$39,999$40,000-$44,999$45,000-$49,999$50,000-$54,999$55,000-$59,999$60,000-$64,999$65,000-$69,999$70,000-$79,999$75,000-$79,999$80,000
+
Income Level
Time (in minutes)
Female, Non-Worker Female, Worker Male, Non-Worker Male, Worker
Time at Other by Income Level
0
50
100
150
200
250
300
350
Less Than$5,000$5,000-$9,999$10,000-$14,999$15,000-$19,999$20,000-$24,999$25,000-$29,999$30,000-$34,999$35,000-$39,999$40,000-$44,999$45,000-$49,999$50,000-$54,999$55,000-$59,999$60,000-$64,999$65,000-$69,999$70,000-$79,999$75,000-$79,999$80,000
+
Income Level
Time (in minutes)
Female, Non-Worker Female, Worker Male, Non-Worker Male, Worker
Time in Travel by Income Level
0
10
20
30
40
50
60
70
80
90
Less Than$5,000$5,000-$9,999$10,000-$14,999$15,000-$19,999$20,000-$24,999$25,000-$29,999$30,000-$34,999$35,000-$39,999$40,000-$44,999$45,000-$49,999$50,000-$54,999$55,000-$59,999$60,000-$64,999$65,000-$69,999$70,000-$79,999$75,000-$79,999$80,000
+
Income Level
Time (in Minutes)
Female, Non-Worker Female, Worker Male, Non-Worker Male, Worker
Time at Activities by Income
10
210
410
610
810
1010
5000 99991499919999249992999934999399994499949999549995999964999699997499979999
+
Household Income ($US1990)
Duration (minutes)
Home, Work
0
20
40
60
80
100
120
140
160
180
Duration (minutes) Shop, Other, Travel
Home Work Shop Other Travel
Time at Work by Age
0
50
100
150
200
250
300
350
400
18-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65
Age
Time (in Minutes)
Male,Worker Female,Worker
Time at Shop by Age
0
10
20
30
40
50
18-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65
Age
Time (in Minutes)
Male, NonWorker Female,NonWorker Male,Worker Female,Worker
Time at Other by Age
0
50
100
150
200
250
300
350
18-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65
Age
Time (in Minutes)
Male, NonWorker Female,NonWorker Male,Worker Female,Worker
Time at Travel by Age
0
20
40
60
80
100
120
18-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65
Age
Time (in Minutes)
Male, NonWorker Female,NonWorker Male,Worker Female,Worker
Time at Home by Age
0
200
400
600
800
1000
1200
1400
18-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65
Age
Time (in Minutes)
Male, NonWorker Female,NonWorker Male,Worker Female,Worker
LifeCycle & Time at HomeTable 3: Life Cycle Stage,Gender, and Activity Duration
TIMEHOMEDifference Difference
Number of Youngest Gender Mean Std Dev of Means of MeansAdults Child Total M-F
1 None Male 933 270 -3.40 -1.881 None Female 971 250 -0.932+ None Male 943 261 -5.64 -4.092+ None Female 982 249 -0.331 0-5 Male 1154 305 1.36 0.891 0-5 Female 1040 247 1.982+ 0-5 Male 932 249 -5.97 -12.882+ 0-5 Female 1084 242 11.241 6-15 Male 1045 298 1.07 1.251 6-15 Female 968 248 -0.692+ 6-15 Male 937 260 -4.71 -6.762+ 6-15 Female 1026 240 4.431 16-21 Male 910 282 -1.05 -1.111 16-21 Female 997 225 0.382+ 16-21 Male 956 258 -2.11 -1.992+ 16-21 Female 993 248 0.651 retired Male 1196 214 3.55 0.361 retired Female 1162 241 2.452+ retired Male 1105 246 6.81 -0.432+ retired Female 1115 232 8.40
TOTAL 984 257
LifeCycle & Time at Work
LifeCycle & Time at Shop
LifeCycle & Time at Other
LifeCycle & Time at Travel
Choice Model
• Logit model to predict share of time between 4 activities (incl. travel to act.) for individuals who undertook all four
• Greatest part of explanatory power is in Activity Specific Constant.
• 2nd most sig = activity frequency
TABLE 1: Models to Predict Travel Duration by Activity Duration and Number
ActivityVisit Other
Home Work Shopping Personal School Doctor Friends Social TOTAL & Related Business Church Dentist Relatives Recreation OTHER
Activity DurationMean 984 492 65.6 89.5 204 85.1 178 150 193
Std. Dev. 257 158 82.7 118.1 161 75.3 147.9 137 168
Travel DurationMean 28.8 24.1 14.7 24.1 17.8 19.1 23.2 23.6 30.2
Std. Dev. 40.1 24.5 17 30.1 14.3 11.9 24.5 28.3 32.7
StopsMean 1.41 1.13 1.27 1.65 1.16 1.07 1.25 1.29 1.84
Std. Dev. 0.69 0.47 0.64 1.08 0.46 0.26 0.6 0.63 1.29
CoefficientsNumber of Stops 7.89 16.90 10.82 11.24 8.63 20.77 14.46 16.40 12.23(t - stat) 12.40 22.93 22.91 20.61 8.57 6.23 13.41 16.36 32.41
Activity Duration -0.024 0.000 0.031 0.028 0.020 0.005 0.027 0.043 0.028(t - stat) -13.623 -0.098 8.334 5.660 7.057 0.415 6.095 9.172 9.668
Constant 41.22 5.18 -0.84 3.22 3.72 -3.51 0.52 -3.78 3.65(t - stat) 20.36 3.61 -1.28 3.07 2.83 -1.00 0.33 -2.76 4.18
N 8038 4287 2589 2260 850 165 1201 1750 4768Adj. R-Square 0.04 0.11 0.22 0.20 0.14 0.20 0.17 0.23 0.24Std. Error 39.42 23.17 15.05 26.89 13.25 10.62 22.41 24.91 31.87F-Stat 181.20 262.91 376.70 291.09 72.56 22.24 123.41 262.42 740.80Sig. F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00note: mean activity duration, travel duration, and number of stops is only for those making trips (number of stops > 1), as are associated regressions
Activity Duration
• Space (density, metro area, region)
• Money (income, work-status, gender)
• Life-Cycle (age, gender, household size, # adults, age of oldest child)
Work Outside Home Work at Home Nonworkers All Persons
M F M F M F M F Total Household
HOME 1968 1.38 1.29 1.46 1.47 1.24 1.33 1.39 1.37 1.38 2.85
1988 1.33 1.34 1.50 1.57 1.60 1.57 1.36 1.42 1.39 2.75
WORK 1968 1.00 1.00 0.00 0.00 0.00 0.00 0.83 0.51 0.68 1.15
1988 1.31 1.21 0.00 0.00 0.00 0.00 1.14 0.55 0.99 1.57
SHOP 1968 0.19 0.21 0.50 0.87 0.36 0.63 0.24 0.52 0.38 0.78
1988 0.22 0.31 0.59 0.88 0.75 0.89 0.29 0.49 0.39 0.78
OTHER 1968 0.48 0.39 1.30 0.88 1.23 1.08 0.65 0.71 0.69 1.65
1988 0.86 1.00 1.76 1.69 1.78 1.91 1.00 1.25 1.12 2.35
TOTAL 1968 3.05 2.89 3.19 3.42 2.90 2.84 3.11 3.11 3.13 6.42
1988 3.72 3.86 3.87 4.36 4.11 4.15 3.79 3.71 3.89 7.45
Mean Activity Frequencies
Work Outside Home Work at Home Nonworkers All Persons
M F M F M F M F Total Household
HOME 1968 820 865 1178 1245 1132 1225 886 1033 961 2114
1988 799 823 1163 1205 1104 1132 844 924 885 1808
WORK 1968 486 459 0 0 0 0 396 243 321 538
1988 466 441 0 0 0 0 400 311 354 563
SHOP 1968 7 10 19 45 24 50 10 30 19 39
1988 10 15 43 48 34 55 14 26 20 41
OTHER 1968 43 28 172 95 210 98 72 63 66 162
1988 64 67 166 126 216 170 82 90 86 202
TOTAL 1968 85 79 70 55 75 67 76 72 72 146
1988 101 93 67 62 86 83 100 89 95 173
Mean Activity Durations
Home
• Time spent at Home dropped for workers and nonworkers, men and women.
• Why?• Mobility, substitution of out-of-
home activities.
Work
• Marked trend in increase time at work.
• Female labor force participation increases
• However, for workers, time at work decreased. Contrast with “Overworked American” argument.
Shop
• With rising income, people should shop more, right?
• However, time available for shopping drops as more women worked.
• So while both workers and non-workers shop more, the overall time spent shopping is steady (increased for men, decreased for women).
• Once again, Weighted Averages help explain our paradox.
Other
• Other: Pickup Drop Off, School, Unspecified other activies (doctor, bank, church, recreation, eating out, etc.)
• Men did more other than women in 1968, less in 1988.
• Overall, there is more time at other activities. Non-work is rising. Nonworkers (as expected) do more nonwork than workers.
Travel
• Time spent traveling has increased sharply.
• Commuting time has held steady.• Thus non-commuting (nonwork) travel
is the source of most rise in travel demand.
• There is no overall travel budget in DC. This is in contrast with other findings for other areas (e.g. Twin Cities, see Barnes and Davis)
References
• Levinson, David and Ajay Kumar (1994). "The Rational Locator: Why Travel Times Have Remained Stable." Journal of the American Planning Association, Summer 1994 60:3 319-332. http://www.ce.umn.edu/~levinson/papers-pdf/doc-locator.pdf
• Levinson, David and Ajay Kumar (1995). "Activity, Travel, and the Allocation of Time." Journal of the American Planning Association. 61:4 458-470. http://www.ce.umn.edu/~levinson/papers-pdf/doc-activity.pdf
• + Levinson, David. 1999. "Space, Money, Life-cycle, and the Allocation of Time." Transportation 26:2: 141-171. http://www.ce.umn.edu/papers-pdf/LifeCycle.pdf
NPTS Data
• 1990/91 and 1995/96 Nationwide Personal Transportation Survey
• 1990 and 1995 Federal Highway Administration Highway Statistics
• Individuals whose total activities did not add to 1440 minutes (24 hrs), excluded
• This study looks only at adults, 18-65 years of age
• Excluded travelers with a daily shopping time greater than 420 minutes
• 1990 Survey 21800 Households, 47000 individuals, 150000 Trips
MWCOG Data
• 1968 and 1987/88 Household Travel Surveys• 1968: 20,000 Households Making 135,000 Trips• 1987/88: 8,000 Households Making 55,000 Trips• For Consistency, Analysis limited to 3 rings
(though 1987 survey examined a somewhat larger area).
• Key Activities: Home, Work, Other• Key Modes: Drive Alone, Carpool (2, 3+), Walk to
Transit, (Park and Ride, Kiss and Ride in 1988),
Mean Travel Time by Mode and Purpose
Work Trips
Home-Based Nonwork
Work-Based Nonwork
Other-Based Other
Drive Alone 1968 30.4 18.5 25.9 17.9
Drive Alone 1988 30.7 19.3 26.2 17.8
Carpool 2 1968 34.4 17.6 26.8 17.1
Carpool 2 1988 31.8 18.4 29.7 17.0
Carpool 3+ 1968 44.0 17.9 33.7 15.1
Carpool 3+ 1988 41.0 15.9 31.8 18.2
Walk to Transit 1968 47.9 41.2 37.7 33.5
Walk to Transit 1988 41.7 36.2 30.8 34.6
Park and Ride 1988 54.3
Kiss and Ride 1988 53.4
Walk 1988 20.1 13.8 15.7 18.6
All Modes 1968 34.5 19.2 27.5 17.6
All Modes 1988 34.2 19.6 27.7 18.5
Myths
1. The long commute is commonplace2. Jobs Housing Balance doesn’t
matter3. ‘Sprawl’ makes congestion worse4. Travel times are rising5. Transit investment will lower travel
times6. Most travel is work trips
Commuting and Non-Commuting
• Rational Locator hypothesis suggests something like a loose commuting time budget.
• Clearly there is a total time budget (24 hours in a day).
• Is there an overall travel time budget?
1988 Distribution by Mode