An Impression Of The Protest

…from Matt Welch, who wandered out to the mall to see it..

[Late evening update]

Per the discussion in comments, a graphical tale of “left” versus “right” events on the mall.

[Late Sunday night update, with a bump]

Henry Vanderbilt (who should start a blog on space transportation and other topics) sends an analysis of the crowd size via email. He says it’s clearly six figures — hundreds of thousands:

I’ve taken a look at the available hard data on the crowd size at yesterday’s DC Tea Party, and (FWIW), by two different crowd-count methods based on two different data sources (one of these including the New York Times report). It’s definitely “hundreds of thousands.” Not “millions”, no, nor mere “tens of thousands” as all the major media outlets are putting it. Hundreds of thousands. Two analyses follow in detail, to allow criticism of the methodology and addition of better data.

Analysis 1: This gives a range of 240,000 to 320,000 marchers down Pennsylvania Ave, and is based on the time-lapse march route video plus measurements of the route taken from Google Maps. The time-lapse sequence was taken from a webcam over Freedom Plaza at 14th St and E NW, looking ESE down Pennsylvania Avenue toward the Capitol. The time-lapse video is 41 seconds long (0-40), is labelled as covering 8 AM to 1130 AM on 9/12/09, and thus scales at just over five minutes real-time per second of video. The video shows the march starting out of Freedom Plaza at 17 seconds (~9:30 AM) with the tail end leaving the plaza at 36 seconds (~11:10 AM). Google Maps sat view, meanwhile, shows Pennsylvania Ave. to be just over 220 feet wide (eight traffic lanes plus sidewalks) along the march route, and the length of the march route from the exit of Freedom Square to where the road reaches the Capitol West Lawn to be just over 4400 feet. The video seems to indicate marchers filled both road and sidewalks for the entire march route for most of the time of the march, FWIW.

The video does not seem to provide enough resolution, spatial or time, to directly measure the rate of advance of the march. The speed with which the route initially fills up shouldn’t be used (the fast ones always end up out front) nor the speed with which it empties (the slow ones are at the back). I’ll make the assumption here that the march averaged 1 mph – large dense peaceable crowds tend to have much internal friction and move slowly, 1-2 mph in my experience; I think 1 mph is mildly conservative.

So we know the crowd took ~100 minutes to march past the east end of Freedom Square on a route ~220 feet wide, and we’re assuming they averaged a 1 mph rate of advance. That would make the entire crowd about 8800 feet long by 220 feet wide (had the route of march actually been that long). In other words, the crowd occupied about 1.94 million square feet at their march density, at an assumed march speed of 1 mph.

We now need a second assumption: how tightly packed the crowd was as they marched.

I estimate that a really tightly jammed crowd (stage-front at a concert) takes about two square feet per person. A dense elbow-to-elbow crowd on the move is three to four square feet per person, and a polite relaxed crowd on the move is six or more square feet per person. This marching crowd seemed very densely packed in the overhead video, but from various closeups I’ve seen it seemed more like 6-8 square feet per person. 1.94 million square feet divided by six square feet per marcher gives about 320,000 marchers; divided by 8 gives about 240,000 marchers.

To sum up, the width of the march route and the time for the march to pass one point are known. The two main assumptions in this crowd estimate are the average speed of the march and the average spacing of the marchers. 1 mph and 6-8 square feet per person seem mildly conservative estimates; based on those we get a crowd size of multiple hundreds of thousands.

Note too that this march-route estimate does not cover anyone who arrived at the march destination by other routes.

Analysis 2: This one gives a range of 330,000 to 500,000 demonstrators in front of the Capitol, and is based on the NYT description of the crowd (“A sea of protesters filled the west lawn of the Capitol and spilled onto the National Mall) plus the first photo in the story at the Daily Mail, showing the Capitol West Lawn during the protest, plus measurements taken from Google Maps sat view of the area.

The overall West Lawn of the Capitol area is a square just over 1500 feet on a side. Between the Reflecting Pool, the Botanic Gardens building, and various other obstructions, I estimate about 75% of that area is actually available for a crowd. That’s comes out to about 1.7m square feet.

The National Mall, meanwhile, consists of eight squares of about 600 by 600 feet each, (about 360,000 square feet each) in a line west to the Washington Monument. I will assume for this analysis that the crowd described by the NYT extended only to the first of these eight blocks, giving us 1.7m + 360K square feet, or about 2 million square feet of crowd.

Crowds at rest take less room than crowds on the move; I therefore assume a range of 4 to 6 square feet per person in this crowd. The above-pointered picture in the Daily Mail seems to support the 4 square feet end of this range, but it was taken from just east of the Reflecting Pond and shows the front portion of the crowd – the crowd density likely drops further back. However, there is also uncertainty about just how far back the crowd goes – at least one attendee claimed in a blog comment that the crowd described by the NYT extended the entire length of the Mall. Applying the 4 to 6 square foot range to the West Lawn plus first block of Mall area seems reasonable for now, absent better data. This gives us an estimated 330,000 to 500,000 demonstrators in front of the Capitol yesterday.

Obviously there are significant error bands in both of these estimates. There’s also room for better data; in particular I’d be interested in any marchers who accurately timed their march from leaving Freedom Square to first arriving at 3rd St where the West Lawn starts, as well as any more info on how far back along the Mall the crowd extended and how dense the crowd was.

I think it’s already very clear, however, that “hundreds of thousands” is the correct description of the size of the 9/12/09 DC protest.

I wasn’t there, but the pictures I’ve seen look like a lot of people. This is the kind of analysis that it would be nice to get from journalists, but most of them went into the profession because (among other reasons) they were told there would be no math.


[Monday updates]

Bruce Webster has thoughts and pictures. And the Gormogons have turned the analysis up to eleven. They think there are on the order of a million people.

[Mid-afternoon update]

Another analysis
over at Pajamas Media. Again, on the order of a million.

[Update on Thursday morning, the 17th]

Pajamas has a new post on the subject.

98 thoughts on “An Impression Of The Protest”

  1. Thank you for a GREAT analysis of the crowd. Oddly enough, it was very important to those of us who were there that day. We all knew it would be under-reported but felt the need to be “validated” by the crowd size, I guess.

    I still haven’t posted pictures, video, and commentary to my own blog but found yours while scouring the internet for a good analysis/estimate of the 9/12 March crowd in DC. THANK YOU for putting some brainwork into coming to a reasonable estimate of the crowd!

    My husband and I drove 10 hours from Kentucky to be in DC for this event. We were marching down Pennsylvania Ave at what you estimated to be the tail end of the march (after 11:10am). I know there were many, many, many more people marching after us because a large number of us were slowed down on our way to the march by the lack of available Metro transit trains, another organization that obviously underestimated the size of this event!

    The start of the march was scheduled for 11:30am but, from what we were told by the organizers, the march started earlier when Capitol Police asked the organizers to forego the starting rally in Freedom Plaza and start the march early at 9 or 9:30 instead. I hear that there were thousands of people at the Plaza ready to go at 8am.

    Your estimates seems right on to me. The crowd was comfortably spaced (unless you weren’t alert, in which case you’d be trampled by others in the march taking video and snapping pics!). While there were many, many people lining the sidewalks on the march route, most of them stayed in place and did not march on to the Capitol with us. A lot of them were wheelchair bound or elderly. It was terrific to see them show their support in a safe way as we did see one wheelchair bound woman suffer a seizure in the middle of the march route — we stopped to help and only moved on when told that EMS was on its way and a nurse and doc were with her to do what they could.

    As for the Capitol lawn — I was very upset when I realized that people could have had room to sit down for a while if the rubber fencing had not been put up at the end of the lawn where it meets the sidewal. (We had to dodge a Capitol cop to jump up over the rubber fencing that was keeping a lot of us off the West Lawn where we were SUPPOSED to be.)

    The crowd toward the back of the lawn was less dense because people couldn’t get through the standing crowd on the sidewalks (just outside the rubber fencing) to get around to an entry point up toward the front of the lawn. The back of the lawn was crowded but it was far less crowded than the sidewalks and parking lots!

    No complaints though. Really! What a wonderful day it was, regardless of the actual numbers. I’m ready to do it again and next time, I will tell myself that numbers don’t really matter as much as we think they do… and then secretly, I’ll just hope you do your analysis again 😉


  2. The crowd was made of GOOD PEOPLE.

    If I had dropped my wallet, I would have got it back with interest.

    Make no mistake about it, they were the good guys (and gals).

    And, they absolutely adore Sarah Palin.

  3. Crowd was not 2 million. I was at the March for Life and that was something like 250-300k.

    This was HUGE. I estimate including early leavers and latecomers, it came to probably the 1.0-1.3 million.

    It was much bigger than I thought. I was hoping for half a million.

  4. There are things soom people did not see,the whole capitol was surrounded all 4 corners.All streets filled.The announcers ask 2 times to clear 1st street behind the capitol.People got there early and were leaving by 2 but the amount to fill there spots were suffient.People just kept comming.Many people could not get there because of metro. buses, streets closed .The only one that knows for sure is home land security fling thier helicpter over head.They wil never tell. But we the people know how many people were thier.Numbers games will only make us stronger.

  5. I was there and am so annoyed that even on Fox, they said tens of thousands. Five minutes ago, O’Reilly said 75,000.

    It is inconceivable to me that there were any less than 200,000, and it felt more like 400,000 to me.

  6. There is no question in my mind that there were hundreds of thousands and probably a million or more, based on Vanderbilt’s analysis as well as my own observations. To wit, we were at the west lawn of the Capitol until about 1:30 when we decided to make our way back to the Metro Center station. As we got closer to the station, we saw fresh “troops” heading in, and in fact when the orange line train arrived to take us back to Dunn Loring, we thought “how are we going to fit?” But there were new marchers pouring out. In fact, by the time we got to our destination back home around 3:00 or so, there were some folks asking us if it was still going on, because they were heading down.
    That time lapse video doesn’t capture it all.

  7. I saw a few snippets on the news and, of course, read several stories on the blogs. It is no surprise that those opposed to the Tea Party concept are trying to down play it. Arguing over numbers is exactly what they want to do, rather than actually consider why people are protesting.

    The fact is, on April 15th, the Tea Party’s were considered a one time event. Then around Memorial Day, we were told they wouldn’t last the summer. There were large crowds on July 4th, but they were compared to average July 4th crowds.

    Well, the Tea Partiers are still around at the start of the 2010 election run up. There is no question that each time an event is held, it is larger than the previous event. All the attempts to marginalize the Tea Partiers have lead to even larger membership. Attempts to demonize the Tea Partiers as just GOP’ers has lead to more true liberals joining the cause. Attempts to call them racists has lead to minorities joining the cause. Claiming they are only against Obama has caused unhappy Obama voters to join the cause.

    I say, keep it up!

  8. That time lapse video doesn’t capture it all.

    Somnething like this is a bit difficult to capture by conventional means — it’s like trying to take a photograph of the Grand Canyon.

  9. 1) Virtually no one was marching on the sidewalks, the street width is 100 ft.

    2) Look into rank and file or military marches, tightly packed is 12.5 sq. ft. per person, normally packed is 25 sq. ft. per person. I’ve used 25 sq. ft. per person as the marchers were highly randomly packed and did not ever form a well ordered column or formation.

    3) I used a higher speed of 3 ft/sec (IMHO high or non-conservative estimate)

    4) Elapsed time of 5700 seconds (based on start/stop frames).

    5) 42 frames total, exactly 300 sec/frame.

    Using the above, a much more realistic estimate of ~68,000 is obtained, that would be a slightly high estimate, given the higher assumed median walking speed.

    6) The Inauguration had 240,000 people in the ticketed areas, the ticketed areas were much more densly packed then this rally, by a factor of 2-3.

    Therefore, at best, this rally had an in situ population of 80,000 to 120,000 people, tops.

    Thus giving a nice round number of 100,000 or O(6).

  10. I agree with your analysis except for the square footage per person. The videos I’ve seen show more like 20-30 square feet per person and a not-very-densely packed road. There is easily 4-5 feet between rows of marchers and another couple feet between them side-to-side, even in the most densely packed sections. There are lots of parked cars, lots of displays set up, lots of empty sidewalks, lots of empty space. Do you have actual video closeups (so we can be sure it’s not a temporary nonmoving glut) that show something different?

  11. I’m still confused.

    I was driving home to Winchester VA from Philadelphia on the 12th, and decided to take a swing through downtown DC so I could see what was going on.

    I arrived around 2:00pm. Managed to drive down Constitution, Pennsylvania, Independence, and passed both Madison and Jefferson. Traffic was no heavier than it usually is on a weekend in that part of town. Didn’t see any large crowds on the Mall; I circled back several times.

    I saw people here and there with signs and such. I thought it was over at that point and people were still hanging around afterward.

    I would think that, if the crowd were in the hundreds of thousands, I would have seen a lot more people, and more streets would have been blocked off. But there weren’t.

    Did I miss something?

  12. p.s. – “The Western Experience” claims that official sources say Pennsylvania Ave. is only 160 feet wide, and the videos show that there are clearly parked cars and demonstration signs all over it, not to mention that the sidewalks are empty most of the time. Want to scale down your estimates even more?

  13. We did it on 9/12.
    It was the tip of the Iceberg…..
    The tip of the spear.

    It will only grow, because Obama and Congress are genetically incapable of keeping their mouths shut.

    Watch as the iceberg rises.

  14. The nominal curb-to-curb width of Pennsylvania Avenue is 100 feet, You can measure it directly from orthophotos (DC Atlas or USGS) or download DC Atlas GIS data in ESRI shapefiles for the roadways for the entire DC (

    One hundred feet. That’s it. Period.

    That’s the maximum roadway width (curb-to-curb) of Pennsylvania Avenue.

  15. I have not ability in estimating crowds but I was there and I can attest to several things:

    1. We arrived at Freedom Plaza at 9:00AM. We started walking to the US Capitol at 10:00am and there were many, many, many people in front of us.

    2. We walked at a very leisurely pace and were not elbow to elbow but it was certainly packed enough that you had to watch where you were walking and it was a dense population. There were also people lined on both sides of the street (not walking) the entire route.

    3. We arrived at the US Capitol somewhere around 11:15 to 11:30am – well I should say within a block of the Capitol where the Santi Cans were located. We had to wait for approximately 30 minutes to use the Johns.

    4. We then stood on the grassy hill for about 30 minutes talking to people. From there we watched bus loads of people stream in from the north side of the Capitol who apparently had been let off from buses.

    5. We could also see people streaming in from the south of the mall area who again apparently had been let off on buses.

    6. We then changed locations, moving to the Mall side of the reflection pond by the arboretum. We stood around the south side of the reflection pool and watched the crowd continue to stream in from the Freedom Plaza area for a good 2 hours (this would be approximately 12:30pm to just after 2:00pm.

    7. We then left the area and had to go down town to eat as there were lines hours long to get into any place around the area that had food and we felt they would probably run out of food before we were eventually served.

    We were told just before we left that the crowd had been estimated by police at 1.5 million. I can guarantee you that what ever the size of the crowd – it has huge, peaceful, friendly, courteous, clean and upset with our lack of representation in Washington DC. These people were your common every day Americans from all across the country.

  16. How many Blacks, Asians, and Latinos were at this rally?

    I’ve looked at literally thousands of images (Flickr keyword 912DC and elsewhere) and can count the total number of minorities that I’ve seen so far on one hand.

    Seriously. Like I was actually looking for minorities even.

    The crowd was overwhelmingly white and the majority were middle aged and older.

    What’s up with that?

  17. Hey, just a quick note to say that the Gormogons have withdrawn our million-people figure, since the main picture we were analyzing turned out to be from a 1997 Promise Keepers’ rally.


    At any rate, the official count for that crowd (as the Park Police still did it back then) was 1.4 million. But as you and our Czar pointed out, the issue of what density one assumes is critical. Likely the 1.4M figure is also (inadvertently) inflated by using too great a density.

    Anyway, thanks for the link, and sorry if we misled anyone. We are currently searching for the fiend who mislabeled the picture. Hideous consequences will ensue. —孔夫子

  18. The crowd was overwhelmingly white and the majority were middle aged and older.

    What’s up with that?

    Well, what’s mysterious about this? That’s the ethnic makeup of this group with a grievance. Are you going to claim their grievances are invalid or the group is even racist because they have too many old white guys in there? Life isn’t a PC bologna commercial.

  19. Just noting the demographics which don’t match the national demographics at all.

    Compare this group (mostly older white conservatives/libertarians) with the 1.8 million group at the Inauguration.

    Which of these two in situ groups more closely fits the national demographics, also known as We The People?

  20. Which of these two in situ groups more closely fits the national demographics, also known as We The People?

    I thought this nation was supposed to be beyond prejudice. Why is this even relevant?

    If the feds were considering legislation to round up left-handed people into prison camps, I’d expect a disproportionate number of southpaws to march on DC. Does this make their grievance less legit because the inauguration “more closely fit” the national demographics of We The People?

  21. Just making sure that the phrase “We The People” doesn’t apply to just a very narrow well defined demographic of people who happen to show up that day.

    That is all.

  22. If you take the phrase in the context as Ken was using it, it applies to “we the people” who were there as opposed to those who were not there and thus are belittling those who were.

    To lift it out of that context and presume that people who were not there are sub-humans who deserve no representation is to invent a pretext for offense.

    To continue the example, if the pundits were to belittle the southpaw march on DC by deflating the numbers, and an attendee were to say that “we the people know how many were there”, it would not mean that right-handed people were not a member of “We The People” as mentioned in the US Constitution or were otherwise less important.

    That is all.

  23. Just making sure that the phrase “We The People” doesn’t apply to just a very narrow well defined demographic of people who happen to show up that day.

    The sincerity just oozes. Eve if it were just old whites, that’s still a large demographic. And calling that demographic “very narrow” is just a racist insult. Caucasian is a huge demographic category. There are probably 2-2.5 billion people who fall in that category including most asian Indians. A lot of those people happen to be “old”.

  24. Seriously. Like I was actually looking for minorities even.

    Racist people do tend to look at the color of people’s skin first before considering the merit of their message.

  25. Racist people tend to self identify with others of their ilk.

    912DC proves that conclusively.

    This is an interesting comment. How does your first sentence work with the second? Are you saying you, being a racist, recognized other racists in the crowd? Or, are you saying that because you saw a large group of white people, you just assumed they were racist? If the latter, are you saying the population of Vermont proves conclusively Vermont is racist?

  26. I’m saing that you should just look into the mirror of reality.

    Oh I see, you look in mirrors and see a racist.

  27. I found the analysis offered here very sophomoric. I have done my own study base on devised methodology and calculation which you can find here:

    It’s backed by evidence (pictures and clips) and determining the boundaries of the protesters and calculation of final tally derived from the density of the crowd at each given block. My calculus puts the figures around 130k up to 160k.

  28. Surprise, UR is just a racist troll. Well, at least this exchange has just demonstrated the futility of reasoing with such people. Remember that for the future, folks.

  29. Surprise, Titus is just a racist troll. Well, at least this exchange has just demonstrated the futility of reasoing with such people. Remember that for the future, folks.

  30. Predictable, but at least the parrot isn’t thread-crapping on the rest of the site, so there’s that ray of sunshine…

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