Crowd Estimation Math submitted by @kescrimg

The women’s march in Washington was roughly three times the size of the audience at President Trump’s inauguration, crowd counting experts said Saturday.

Marcel Altenburg and Keith Still, crowd scientists at Manchester Metropolitan University in Britain, analyzed photographs and video taken of the National Mall and vicinity and estimated that there were about 160,000 people in those areas in the hour leading up to Mr. Trump’s speech Friday.

They estimated that at least 470,000 people were at the women’s march in Washington in the areas on and near the mall at about 2 p.m. Saturday.

For the women’s march, they chose a period in time when the crowd was moving the least, from 1:30 p.m. to 2:15 p.m. Using aerial footage and photographs from various angles, the analysts isolated areas with an average density of 2.5 people per square meter, the same method used at Mr. Trump’s inauguration the day before.

The Park Service said in 2009 that it “firmly” believed that Mr. Obama had drawn the largest crowd ever to the National Mall. The location could have also been a contributing factor for the crowds that year; about half of Washington’s population is black, and more than 92 percent of the city voted Democratic.

Mr. Spicer said that the area between the platform where Mr. Trump was sworn in and the Washington Monument could hold 720,000 people, and claimed that “all of this space was full when the president took the oath of office.”

The images below, captured 45 minutes before the respective oaths of office, show areas that were crowded with people at Mr. Obama’s inauguration that were clearly empty during Mr. Trump’s.