Texas A&M Transportation Institute released their annual Urban Mobility Report.
http://mobility.tamu.edu/ums/ (http://mobility.tamu.edu/ums/)
The report includes a new measure from previous years known as the Planning Time Index (PTI) which attempts to determine how much time you must leave if you wish to be on time 19 out of 20 trips. Also lists the typical Travel Time Index (TTI) for each metro that has been included in previous years.
Travel Time Index–The ratio of travel time in the peak period to the travel time at free-flow conditions. A value of 1.30 indicates a 20-minute free-flow trip takes 26 minutes in the peak period.
Planning Time Index–A travel time reliability measure that represents the total travel time that should be planned for a trip. Computed with the 95th percentile travel time, it represents the amount of time that should be planned for a trip to be late for only 1 day a month. Computed with the 80th percentile travel time (PTI80), it represents the amount of time that should be planned for a trip to be late for only 1 day a week. A PTI of 3.00 means that for a 20-minute trip in light traffic, 60 minutes should be planned (20 minutes x 3.00 = 60 minutes).
Travel Time Index (TTI) of major metros (over 3 million):
1.37 Los Angeles-Long Beach-Santa Ana CA
1.33 New York-Newark NY-NJ-CT
1.32 Washington DC-VA-MD
1.28 Boston MA-NH-RI
1.26 Houston TX
1.26 Philadelphia PA-NJ-DE-MD
1.26 Seattle WA
1.26 Dallas-Fort Worth-Arlington TX
1.25 Chicago IL-IN
1.25 Miami FL
1.24 Atlanta GA
1.22 San Francisco-Oakland CA
1.18 Detroit MI
1.18 San Diego CA
1.18 Phoenix-Mesa AZ
Planning Time Index (PTI) of major metros (over 3 million):
5.72 Washington DC-VA-MD
4.95 Los Angeles-Long Beach-Santa Ana CA
4.44 New York-Newark NY-NJ-CT
4.25 Boston MA-NH-RI
4.00 Dallas-Fort Worth-Arlington TX
3.99 Seattle WA
3.95 Chicago IL-IN
3.74 San Francisco-Oakland CA
3.71 Atlanta GA
3.67 Houston TX
3.60 Miami FL
3.46 Philadelphia PA-NJ-DE-MD
3.22 Detroit MI
3.19 Phoenix-Mesa AZ
2.90 San Diego CA
Yearly Delay per Auto Commuter
67 Washington DC-VA-MD
61 Los Angeles-Long Beach-Santa Ana CA
61 San Francisco-Oakland CA
59 New York-Newark NY-NJ-CT
53 Boston MA-NH-RI
52 Houston TX
51 Atlanta GA
51 Chicago IL-IN
48 Philadelphia PA-NJ-DE-MD
48 Seattle WA
47 Miami FL
45 Dallas-Fort Worth-Arlington TX
40 Detroit MI
37 San Diego CA
35 Phoenix-Mesa AZ
Washington D.C. is the big winner this year in the crappy traffic index.