Ahead of the 2017 observance of the anniversary of the Sept. 11 attacks, CNN compiled a list of statistics around the attacks and their aftermath.
19: Hijackers of four fuel-loaded U.S. commercial airplanes bound for West Coast destinations
2,977: People killed in New York City, Washington, D.C., and outside Shanksville, Pa.
2,753: People killed at the World Trade Center (WTC) site in Lower Manhattan
343: New York City firefighters who died in the initial attacks and subsequent collapse of the WTC towers
23: New York City police officers who died
37: Port Authority officers who died
2: Age of youngest victim
85: Age of oldest victim
184: People killed when hijacked American Airlines Flight 77 crashed into the Pentagon
40: Passengers and crew killed when United Flight 93 crashed near Shanksville, Pa.
1,641: WTC victims’ remains positively identified as of August 2017
$500,000: Estimated amount of money it cost to plan and execute the attacks
$123 billion: Estimated economic loss during the first two to four weeks after the WTC towers collapsed in New York City, as well as decline in airline travel over next few years
$60 billion: Estimated cost of the WTC site damage, including surrounding buildings, infrastructure and subway facilities
3.1 million: Hours of labor to clean up 1.8 million tons of debris
$750 million: Total cost of cleanup
22: Governmental agencies rolled into a single Department of Homeland Security, including the Customs Service, the Immigration and Naturalization Service, the Coast Guard and the Federal Emergency Management Agency, after 9/11