(CNN Business) The federal government is running up its credit bill again.

The deficit rose to $779 billion in fiscal year 2018, up 17% from last year, according to final figures released Monday by the Treasury Department. That's the largest number since 2012, when the country was still spending massively to stimulate an economy struggling to recover.

Government receipts were flat this year from last year. Corporate tax collections fell $76 billion, or 22%, due to the Republican-backed tax cut . But that drop was more than offset by increased revenues from individual and self-employment taxes. The fiscal year ended September 30.

Spending rose 3% over the previous year, fueled in part by increases to the defense budget agreed upon in September 2017 as part of a deal between Republicans and Democrats to head off a government shutdown. Social Security and interest on the federal debt also contributed to the increase.

The Committee for a Responsible Federal Budget, a think tank that warns of the dangers of rising debt levels, said the deficit could reach $1 trillion as soon as next year. That would still be below a high of $1.4 trillion reached in 2009, but in a vastly different economy.

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