How Many People were there at 9/12 DC?

Some bloggers are trying to use Metro rail rider ship numbers to show how many people attended the 9/12 DC rally.

http://littlegreenfootballs.com/article/34691_Again_With_the_Grossly_Inflated_Numbers

It does not seem like an accurate way to calculate the crowd to me but let us take a look at the numbers:

Saturday September 13, 2008 362773

Saturday September 12, 2009 437624

Giving a difference of 74,851 rides, but that isn’t the whole story. One thing that may be a factor is that the Labor Day Holiday took place 6 days later in 2009 than in 20008. It may also be note worthy that rider ship is trending down for 2009. But there was also the National Black Family Reunion held 9/12and 9/13. Let’s look at a larger sample:

http://www.wmata.com/rail/disruption_reports/archived_service_reports.cfm

Saturday August 30, 2008 335,945

Labor Day September 1, 2008 227,323

Saturday September 6, 2008 202,528

Saturday September 13, 2008 362,773

Saturday September 20, 2008 360,571

Average Saturday 315,454

Saturday August 29, 2009 303,997

Saturday September 5, 2009 300,963

Labor Day September 7, 2009 165,791

Saturday September 12, 2009 437,624

Saturday September 19, 2009 332,293

Average Saturday 312,417

If we measure rider ship from 9/12 against the average from 2008 then there is an additional 122,170 riders. If we measure rider ship from 9/12/09 against 9/6/09, the Saturday after Labor in 2008, then there is an additional 235,096 riders. Now I must repeat that I do not believe that this is an accurate way to estimate the number of the crowds attending the 9/12 rally. I post this to show what I see as an attempt to cherry pick facts so as to make an argument that the 9/12 rally in DC was not as large as members of the Tea Party movement claim. This argument is an attempt to show that the Tea Party movement is lying, and self aggrandizing. As a corollary of that argument, the fewer people that attended the rally the greater the impact those racist whom did attend and displayed obscene signs.

UPDATE

The Internet is a snooze you loose type of place. I waited to make this post and see that Mr. Tim Blair has posted much of the facts that I posted:

http://blogs.news.com.au/dailytelegraph/timblair/index.php/dailytelegraph/comments/bigness_ensmallened/

And Charles Johnson has fired back:

http://littlegreenfootballs.com/article/34719_Again_with_the_Grossly_Inflated_Numbers_Part_Deux

This is the kind of stuff that makes politics fun.