Conservative bloggers and media continue to insist without the benefit of actual facts that there were millions of tea party protesters on the Mall last Saturday. Here's another data point that makes these claims quite inconvenient.
According to the Washington Metro Area Transportation Authority (WMATA), 437,624 people rode on the Metro Rail system on Saturday, September 12th. How does that day compare to similar Saturdays?
September 5th, 2009: 300,963 riders
August 29th, 2009: 303,997 riders
August 22th, 2009: 293,200 riders
So, was Metro ridership up on the day of the protest? Sure. but the increase in riders could at best be charitably described as modest (and surely some of those riders were participants in the National Black Family Reunion event).
By comparison the Metro ridership for President Obama's inauguration - an event where most counts put the attendee count at above 1 million - was 1,120,000. This was described by WMATA as "the highest ridership day ever in the transit authority's history".
No recent events have been described this way by the Transportation Authority.