ITE's Trip Generation Manual, 9th Edition - Comparison Spreadsheet

UPDATE - The executive director from ITE called me and then followed up with an email stating he believes I have violated their copyright by posting my analyses.  My lawyer doesn't think so, but I'm not going to fund a Supreme Court case on blogging law.  So I'm voluntarily taking down the spreadsheet.  Feel free to email me at mspack@spackconsulting.com if you want to chat about my analysis or if you need help with trip generation.  

In any event, this has made me think a lot about ITE.  I'm a loyal Fellow of the Instituite and a past president of the North Central section of ITE.  ITE has played a huge role in my career.  We've even contributed data at no charge to the Trip Generation Manual.  I'll have a follow-up post before the end of the year with thoughts on possible reforms to ITE.

Here is a spreadsheet that compares the data in ITE's recently released 9th Edition of Trip Generation Manual versus the older 8th Edition - REMOVED.

Based on the analysis worksheet, I draw the following conclusions from the changes (outside of the new land use codes or new independent variables where no comparison can be drawn):

• Residential - Almost the same, with a very slight change downward
• Office - Almost the same
• Retail - Slight trend downward
• It turns out the trip generation rates/distribution percentages haven't changed for about two thirds of the overall data set (independent variable sheets of each land use code).

We've done our best with the data entry in the spreadsheet, but I definitely don't warrant it's accuracy/completeness and would love to hear back if you find any typos.  We're putting this out there so you can compare the data yourselves and to crowd-source improving it.

Also, I'm fighting a cold and I'm not 100%.  Let me know if you draw different conclusions.

 

Comments

[Tristate Traffic Engineer]

I really appreciate your blog. What a great resource. Thank you!

[Ahmed Elsherif]

Mike,

Thank you for this spreadsheet, this is my first time using the trip generation manual i am a student at Ryerson University. I was wondering if you could explain what the columns labelled "weekday", "am", and "pm" represented.

Thank you,

Ahmed Elsherif

[Mike]

Ahmed,
Daily = vehicle trips per day generated.
AM = vehicle trips generated during the 60 busiest minutes during the morning peak period between 7-9 am.
PM = vehicle trips generated during the 60 busiest minutes during the evening
peak period between 4-6 pm.
Mike

[Dave Snelting]

Mike, I too am a loyal member of ITE but your call from the Executive Director about copyright violations is disturbing. Now we inhibit the furtherance of the profession by waving the copyright laws?

[Edward J. Kant, P.E.]

Mike:

I am having a problem trying to equate a comparison of 8th Ed. numbers with 9th Ed. numbers as having anything whatsoever to do with copyright violations. In my 50+ years of practice I cannot count the number of times I have, in analyses, reports, presentations, etc., made comparisons or looked at differences in a number of professional publications as they change over the years.

In fact, several years ago, I authored the update to the Trip Generation Professional Development Modules for ITE and, subsequently, made a number of presentations to local ITE chapters, ACSE , and APWA to educate them on the updates and changes from the 7th Ed. to the 8th ed.

I would be most interested in knowing what rationale Tom used in claiming a "copyright violation."

BTW, I believe your post on the ITE Community will stir some vigerous thought and comment and I applaud you for taking a forward-looking view.

Ed Kant

Edward J. Kant, P.E.
Semi-retired and still practicing
(some day I'll get it right...)

[Mike]

Ed,
I've invited Tom to post his rationale on this blog. So maybe we'll get more details.
Mike

[Ezra Justin Lee]

Hi Mike,

I'm an urban planning grad student at UCLA doing transportation research. Strangely this ITE TG data is inaccessible (unless you're fine with settling for versions from many years ago). Would you be willing to share a copy of the file?

Thanks,
E