- 23: Number of years since Osama bin Laden co-founded al-Qaida in 1988 (BBC timeline)
- 3,460: Approximate number of people killed in the 9/11 attacks in New York, Pennsylvania and Washington, D.C., including firefighters and paramedics (New York Magazine/Guardian)
- 20: Percentage of Americans who knew someone "hurt or killed" at the World Trade Center (New York Magazine)
- 422,000: Estimated number of New Yorkers with symptoms of PTSD post-9/11 (New York Magazine)
- 26: Number of days after 9/11 that the U.S. started bombing Afghanistan (Guardian)
- 1,566: U.S. military fatalities in Afghanistan, Pakistan and Uzbekistan since the beginning of Operation Enduring Freedom (iCasualties.org)
- 100,598 - 109,895: Recorded civilian deaths in Iraq since 2003 (Iraq Body Count)*
- $300 million: Cost, per day, of the Afghan war (AFP)
- $1.3 trillion: Approximate total cost of "wars, extra security measures, and veterans' health care" since Sept. 11, 2001 (March 2011 Congressional Research Service via Salon)
- 97,000: Approximate number of troops currently serving in Afghanistan (AFP)
- One-third: Rough proportion of respondents to a 2006 USA Today/Gallup poll who said they thought U.S. Muslims were sympathetic to al-Qaida (USA Today)
- One-half: Proportion of Arab-American adults who showed symptoms of clinical depression in a 2006 survey conducted by Yale psychologist Mona Amer (the average proportion in a race-blind group is one-fifth) (USA Today)
- Almost 116: Number of months between 9/11 attacks and death of Osama bin Laden
*Official civilian death counts are not kept for Iraq or Afghanistan. Iraq Body Count tallies only civilian deaths reported in the English-language media and select translated sources, or confirmed through "careful review and integration of hospital, morgue, NGO and official figures" -- and is thus considered by many to significantly underestimate the true figure.
Reader note : We'll update this digest throughout the day. Submit your own figures for inclusion in the Comments section.