He bought the Eastern Airlines shuttle for $365 million; it never made a profit, and he spent more than $7 million a month to keep it flying. His new Trump Taj Mahal Hotel and Casino, opened in 1990 with more than $800 million in debt, sucked revenue from his other casinos, pulling them along into the red.

And so, year after year, Mr. Trump appears to have lost more money than nearly any other individual taxpayer, according to the I.R.S. information on high earners — a publicly available database with taxpayers’ identifying details removed. Indeed, in 1990 and 1991, his core businesses lost more than $250 million each year — more than double those of the nearest taxpayers in the sampling for those years.

The tax code allows owners of commercial property to write down the cost of their buildings — a valuable tax shelter known as depreciation. In “The Art of the Deal,” Mr. Trump cited one of his Atlantic City casinos to show how it works. Built for $400 million and depreciated at a rate of 4 percent a year, he said, it could allow him to shelter $16 million in taxable income annually. But Mr. Trump’s example, meant to demonstrate the magic of depreciation, shows something else: Depreciation alone cannot account for the hundreds of millions of dollars in losses he declared on his taxes.

3. He paid no federal income taxes for eight of the 10 years

Business owners like Mr. Trump may also use their losses to avoid paying taxes on future income. Over the years, those losses rolled into a $915.7 million free pass, known as a net operating loss, that appeared on his 1995 tax returns, pages of which were mailed anonymously to The Times during the 2016 campaign.

The new tax information shows how Mr. Trump’s net operating losses snowballed, reaching $418 million in 1991. That was fully 1 percent of all the losses that the I.R.S. reported had been declared by individual taxpayers that year.

And the red ink continued to accumulate apace. In all, Mr. Trump lost so much money that he was able to avoid paying any federal income taxes for eight of the 10 years.

4. He made millions posing as a corporate raider — until investors realized he never followed through

For a time, Mr. Trump was able to stave off his coming collapse with the help of a new public role: He traded on his business-titan brand to present himself as a corporate raider. He would acquire shares in a company with borrowed money, suggest publicly that he was contemplating a takeover, then quietly sell on the resulting bump in the stock price. An occasional quote from a high-profile associate helped burnish the myth.