The numbers, the costs, the effects are astounding.

According to the College Board, 857 students drop out of high school every hour of every school day.

But that's only one statistic. Here are some other numbers that drive home the impact of the high school dropout problem in the U.S.

Dropout rates

About 1 in 4 high school students does not graduate from high school with his or her class.

Nearly 4 in 10 minority students do not graduate with their class.

Employment

Among adults over 25 without a high school diploma in 2011: 14.1 percent unemployment rate

With a high school diploma: 9.4 percent unemployment rate

Earnings