Diane Sawyer‘s report on America’s children living in poverty in Appalachia gave “20/20″ its biggest audience on a Friday night in nearly 4 1/2 years — since Sept. 24, 2004.

“20/20″ won the 10pm hour with 10.9 million Total Viewers and won in all Adult demos as well: A18-34, A18-49 and A25-54. ABC beat second-place CBS by nearly 2 million viewers in the hour. “20/20″ also topped the combined deliveries of CBS’s “Num3ers” and NBC’s “Dateline” at 10pm by 10% in the A18-49 demo.

Last night was ABC’s highest-rated Friday in that demo since November 2007.