WHEN President Bush sent his new budget to Congress yesterday, he trumpeted a continuing decline in the deficit and projected a swing back into the black by 2012.

But the accounting in the thick volumes issued by his Office of Management and Budget bears about as much similarity to the practices of private sector companies as Sanskrit does to Chinese. For sometimes obscure and sometimes political reasons, the federal government reports its finances in a way that portrays them far more favorably than they deserve.

The “official” deficit figure for the 2006 fiscal year is just under $250 billion. But a more accurate calculation would indicate a deficit nearly three times higher, and that is even without including some vast obligations the government owes. And while a strong economy is pushing down that headline deficit, the government’s financial commitments actually grew more rapidly last year than in 2005.

In fact, the federal government itself obliquely acknowledges this chimera in a flotilla of other reports, including the obscure Financial Statement of the United States, prepared by the Government Accountability Office using methods closer to what a shareholder would find in an annual report.