Inauguration | By the numbers

2 million: people at the National Mall
1861: year in which Lincoln was sworn in, with the same Bible Obama used
15: number of times Obama used the word nation in his address
72: percent of Americans that say the country will be better off in four years
34: percent approval rating for George W. Bush
8,000: police officers present
10,000: National Guard troops present
1,000: FBI personnel present
200: guests who attended the inaugural luncheon
67: percent of Americans that said they planned to watch the ceremony
710: days since Obama announced his bid for the presidency
27: degrees outside in Washington, D.C.
10: number of official inaugural balls throughout the night

—compiled from CNN.com, USAtoday.com, Gallop and the Pew Research Center by Sarah Butrymowicz