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The Work Trip The Work Trip in the Context of Daily Travelin the Context of Daily Travel
Census Data for Transportation Planning Conference,
May 2005
Nancy McGuckin, Travel Behavior Analyst
Nanda Srinivasan, Cambridge Systematics
Q: How Important is the Work Trip to Q: How Important is the Work Trip to our Understanding of Daily Travel?our Understanding of Daily Travel?
Overall, one out of five trips and one out of four miles are traveled in commutes.
For workers, over 40 percent of miles and minutes of travel on weekdays is spent in commutes.
Commuting continues to predominate weekdays and peak periods, (nearly 72 percent of workers depart between 5:00 and 9:00 am) contributing to congestion.
The proportion of direct (non-stop) trips to work continues to decline. In 2001, over half of commuters made non-work trips during their commutes.
Work Trips Have Declined Work Trips Have Declined as a Proportion of All Tripsas a Proportion of All Trips
Work Travel as a Proportion of All Travel
0%
10%
20%
30%
40%
1969 1977 1983 1990 1995 2001*
Person Trips Person Miles of Travel Vehicle Trips Vehciles Miles of Travel
Other Types of Trips are GrowingOther Types of Trips are GrowingFaster than Work TripsFaster than Work Trips
Added Annual Trips per Person by Purpose 1990 - 2001
0
5
10
15
20
25
30
35
40
45
50
To/From Work Family & Pers Errands Shopping Soc/Rec (inc Visit)
Add
ed A
nnua
l Trip
s pe
r P
erso
n
Workers Account forWorkers Account for A LOT of Daily TravelA LOT of Daily Travel
Comparison of Travel by Workers and All Others 16+
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Population Tripmakers Person Trips Vehicle Trips PMT VMT Sum of All TravelTime
Workers All Others 16+
Workers do More Workers do More Than CommutingThan Commuting
Proportion of Work- and Non-Work Trips Made byWeekday Workers
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Person Trips Vehicle Trips PMT VMT PMT IN POV SUM OF ALL TT
Work Trips Non-Work
Even When They HaveEven When They Have Long CommutesLong Commutes
0
20
40
60
80
100
120
140
<15 mins 15-29 mins 30-44 mins 45+ mins
Commute Time Categories
Wee
kday
Min
utes
of
Tra
vel
Work Tours NonWork
Less Than Half of CommutersLess Than Half of CommutersMake Direct Trips to WorkMake Direct Trips to Work
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Sun Mon Tue Wed Thu Fri Sat
Mea
n H
BW
Trip
s
1990 2001
The Mountain of Growth in The Mountain of Growth in is in Non-Work Travelis in Non-Work Travel
Difference in Number of Trips by Time of Day, 1990 - 2001
-5.00E+09
0.00E+00
5.00E+09
1.00E+10
1.50E+10
2.00E+10
2.50E+10
Mid-6am 6 - 9am 9-noon noon-3pm 3 - 6pm 6 - 9pm 9 - Mid
HBW HBShop HBSoc HBO NHB
Using Work Tours Using Work Tours Captures More Realistic PictureCaptures More Realistic Picture
0
0.5
1
1.5
2
2.5
Sun Mon Tue Wed Thu Fri Sat
Me
an
HB
W o
r W
ork
To
urs
/Wo
rke
r
HBW Trips Work Tours
We Think We KnowWe Think We Know w whathat
Complex Work Tours Look LikeComplex Work Tours Look Like
Home
Work
Boss’ Birthday
Lunch
Drop Child At Daycare
Pick -up Present for Boss’ Birthday
Pick -up Groceries for Dinner
Pick Child up at Daycare
,
Home
Work
Trip 3 -Shop
Trip 2 –Drop Child at Camp
Trip 4 – Back to Work
Trip 7 –Shop to Home
Trip 8 –Home to Pick -up Child
Trip 1 – Home to Work
Trip 6 –Shop to Shop
Trip 5 – Work to Shop
But, Do We Really?But, Do We Really?
Real Life is MessyReal Life is Messy
Trip 1: To Work
Trip 2: Work to Childs Day Camp
Trip 3: Day Camp to Store
Trip 4: Store to Work
Trip 4: Work to StoreTrip 6: Store to Home
Trip 5: Store to Store
Trip 7: Home to Day Camp
HOME
WORK
360010135.02
360010137.03
360010136.01
360010138.01
360010136.02
360010137.05
360010137.07
360010135.03
360010135.06
360010004.01
360010138.02
360010003.00
360010130.00
360010139.02
360010146.09
360010140.01
360010139.01
360010146.08
360010137.06
360010004.03
360010140.02360010004.04
360010146.07
360010129.00
360010146.10
360010001.00360010007.00360010018.02 360010002.00
But, Is a Good Household Travel SurveyBut, Is a Good Household Travel Survey Good Enough?Good Enough?
Unique pairs of Worker Residence and Work Location Tracts, n=445
Not for Small-Area GeographicNot for Small-Area Geographic CoverageCoverage
Unique pairs of worker residence and workplace locations, n=8,953
HTS Overstates Some Potential Flows HTS Overstates Some Potential Flows and Misses Others Completelyand Misses Others Completely
Legend
NHTS FlowsDAILY_WORK
31 - 200
201 - 400
401 - 600
601 - 800
801 - 1800
Total Workers Trips into Albany=106,058)
Journey-to-Work Flows Journey-to-Work Flows
More ReasonableMore ReasonableTotal Work Flows into Albany=218,715
In major characteristics, In major characteristics,
Census data matches ‘real’ commutesCensus data matches ‘real’ commutes
How usual is a ‘Usual’ day: Mode of travel matched for over 70 percent of commutes
Travel time matched better for workers with short commutes (70 percent) than with long travel times (30-50 percent)
Departure time also very, very similar
Best of All Possible Worlds:Best of All Possible Worlds:
Work flows at small-area geography
AND
Descriptions of the real-life travel behavior from a household travel survey
ConclusionConclusion What makes the JTW invaluable?
It is the work trip data collected in conjunction with the residence and workplace locations with such precise geographic detail.
Transportation planners can evaluate potential work travel at small-area geography While using other data sources to expand their
understanding of the work trip to the whole of daily travel.
ConclusionConclusion
The journey-to-work data are still relevant and needed for small-area planning, and are widely used by transportation planners and analysts.
There is a particular need for these data in areas that do not have a local, current household travel survey.
Looking ForwardLooking Forward ACS will result in fewer flows, and fewer OD
pairs
Planners hope that they can learn to make these data as useful and relevant as the CTPP
This conference is a good overview of issues (e.g. confidentiality and thresholds, sample sizes, uses in modeling)
Guidebook will be vital in helping local planners
We Need to Connect We Need to Connect Workplace Data to Daily Trip-makingWorkplace Data to Daily Trip-making
Journey-to-work flows are not trips
LED promises comprehensive employment summaries, but not trip attraction rates
For instance, 15 employees at a small fast-food place can attract 1500 daily trips
We need to know the 1500, not just the 15