With three weeks still to go in the fiscal year, the federal government already has notched its fourth straight trillion-dollar deficit, the Congressional Budget Office said Monday.

CBO, which releases estimates each month, said the government ran a $192 billion deficit in August, putting the federal government $1.17 trillion in arrears for fiscal 2012, which ends Sept. 30.

The $192 billion deficit was the worst August on record, though the total deficit so far this year is actually lower than it was in 2011, when it stood at $1.23 trillion after 11 months.

CBO said rising wages have brought more tax revenue into the government this year, while new spending has risen at a slightly lower pace, which explains the declining deficit. Spending on Medicaid and unemployment benefits both dropped as heightened stimulus spending ended, and lower costs for the wars in Afghanistan and Iraq also have meant less spending on defense.

But Social Security is up 6 percent and Medicare spending is up 4 percent compared with 2011, CBO said.

The deficit is down significantly from 2009’s record $1.4 trillion.

But CBO in a report last month predicted the government will flirt with yet another trillion-dollar shortfall next year.