Update: This article will be updated with 2017 ridership numbers including that from President Trump’s Inauguration when WMATA’s site goes back up.
One of the most objective measures of crowd sizes at rallies and events held in Washington, DC is metro ridership data from the Washington Metropolitan Area Transit Authority (WMATA). They have released daily ridership data every day since 2004.
For this analysis, we are looking at changes in ridership data on a given weekday. The highest ridership day in WMATA history was for Obama’s first inauguration on Tuesday 1/20/2009. On that day WMATA saw 1,120,000 rides, an increase of 363,000 vs. the previous Tuesday.
The Women’s March on Washington and many other protests were held on 1/21/2017. At the writing of this article the WMATA data site was down and data from 2017 was unavailable. However, on 1/22/2017, WMATA tweeted the ridership data for The Women’s March as 1,001,616 rides . The highest ridership on a Saturday in January 2016 (1/30/2016) was 270,000 rides. If we use 270k rides as a baseline, the Women’s March saw an increase of 731,616 rides.
Table 1: Highest recorded ridership numbers on WMATA on a given day. President Obama’s First inauguration had the highest number of total rides.
| Date | Total Rides | Event |
| 1/20/2009 | 1,120,000 | Obama’s First Inauguration |
| 1/21/2017 | 1,001,616 | Women’s March |
| 6/23/2010 | 894,000 | |
| 4/2/2010 | 876,000 | |
| 4/10/2013 | 872,000 | |
| 1/19/2009 | 867,000 | |
| 4/1/2010 | 867,000 | |
| 4/7/2010 | 857,000 |
Table 2: Day of week averages from 2004-2016. Wednesday tends to have the highest numbers of riders.
| Day of Week | Average Rides |
| Sunday | 209,655 |
| Monday | 619,587 |
| Tuesday | 699,001 |
| Wednesday | 708,027 |
| Thursday | 699,165 |
| Friday | 682,712 |
| Saturday | 314,340 |
Table 3: Highest ridership numbers compared to averages for each weekday from 2004-2016. The Women’s March had the highest deviation from average ridership.
| Date | Total Rides | Deviation from Average | Event |
| 1/21/2017 | 1,001,616 | 689,083 | Women’s March |
| 10/30/2010 | 788,000 | 475,467 | Rally to Restore Sanity and/or Fear |
| 1/20/2009 | 1,120,000 | 420,999 | Obama’s First Inauguration |
| 1/18/2009 | 594,000 | 384,345 | |
| 4/4/2009 | 694,000 | 381,467 | |
| 4/11/2015 | 683,000 | 370,467 | |
| 7/4/2010 | 562,000 | 352,345 | |
| 4/3/2010 | 641,000 | 328,467 | |
| 4/12/2014 | 638,000 | 325,467 | |
| 7/4/2009 | 613,000 | 300,467 | |
| 3/29/2008 | 569,000 | 256,467 | |
| 4/13/2013 | 563,000 | 250,467 |