From the White House to the Treasury to Capitol Hill, everyone's been trying to guess what the government's deficit will be for the current fiscal year.

Estimates range from $43 billion (the "official" Office of Management and Budget prediction) to $70 million (in administration officials' testimony) up to $100 billion and beyond.

All such forecasts have to be considered mere guesstimates--but now the Treasury Department has produced the first actual statistic that might help gauge how far into the red the government will run this year.

For the month of October, the first month of fiscal 1982, Treasury reports, the government took in $45.5 billion and spent $63.6 billion, running up a one-month deficit of $18.1 billion.

October is generally a costly month for the government--little revenue and lots of spending--and in past years it has produced about 30 percent of the full year's deficit.

If this year was an ordinary year, the October results would point toward a deficit just over $60 billion for this fiscal year. But this year is far from ordinary--many large tax cuts don't take effect until January and no one can accurately predict when the economy will begin to turn around. And besides, Congress and the president haven't decided yet exactly how much they're going to spend this year.