A record 18.3% of the nation’s total personal income was a payment from the government for Social Security, Medicare, food stamps, unemployment benefits and other programs in 2010. Wages accounted for the lowest share of income — 51.0% — since the government began keeping track in 1929…

Americans got an average of $7,427 in benefits each in 2010, up from an inflation-adjusted $4,763 in 2000 and $3,686 in 1990. The federal government pays about 90% of the benefits.

“What’s frightening is the Baby Boomers haven’t really started to retire,” says University of Michigan economist Donald Grimes of the 77 million people born from 1946 through 1964 whose oldest wave turns 65 this year. “That’s when the cost of Medicare will start to explode.”