Trump once revealed his income tax returns. They showed he didn’t pay a cent.

The last time information from Donald Trump’s income-tax returns was made public, the bottom line was striking: He had paid the federal government $0 in income taxes.

The disclosure, in a 1981 report by New Jersey gambling regulators, revealed that the wealthy Manhattan investor had for at least two years in the late 1970s taken advantage of a tax-code provision popular with developers that allowed him to report negative income.

Mitt Romney Sees Only One Possible Explanation For Why Trump Won’t Release His Tax Returns

No stranger to questions about his taxes and wealth, former GOP presidential nominee Mitt Romney on Wednesday criticized Donald Trump’s decision to withhold his tax returns from the public, calling the move “disqualifying” and speculating that Trump is hiding “a bombshell.”

Trump, the presumptive Republican nominee, on Tuesday told the Associated Press that he does not plan to release his tax returns — as is tradition for candidates for elected office — because he is being audited.

The Hypocrisy Of Trump’s Refusal To Release His Tax Returns

In an interview with the Associated Press, presumptive Republican nominee Donald Trump revealed that he will not release any of his tax returns before election day.

Previously, Trump blamed an ongoing audit for his failure to release returns, an excuse that was questioned by tax experts. As recently as Sunday, Trump pledged to release the returns “as fast as the auditors finish.” Last October, Trump said he would release his tax returns once Hillary Clinton released her emails. Now, Trump adds that he’s not planning to release them because “there’s nothing to learn from them” and voters aren’t interested in the information.

Marco Rubio Only Released Partial Tax Returns In The Past

As GOP hopeful Donald Trump was under fire during Thursday's Republican debate for not disclosing his tax returns, Sen. Marco Rubio (R-Fla.) vowed that he would release his own tax returns from 2010-2014 this weekend.

What about Rubio's older tax returns? "We already have [released tax returns] going back to 2005 or 2004," Rubio said on Feb.16.

Mitt Romney Thinks Donald Trump Releasing His Tax Returns Might Be A 'Bombshell'

Former Massachusetts governor and 2012 GOP presidential nominee Mitt Romney on Wednesday called on real estate mogul Donald Trump, the GOP front-runner in the 2016 race, to release his tax returns.

New Tax Return Shows Karl Rove's Group Spent Even More On Politics Than It Said

On its 2012 tax return, GOP strategist Karl Rove's dark money behemoth Crossroads GPS justified its status as a tax-exempt social welfare group in part by citing its grants of $35 million to other similarly aligned nonprofits. (Here's the tax return itself, which we detailed last week.)

The return, signed under penalty of perjury, specified that the grants would be used for social welfare purposes, "and not for political expenditures, consistent with the organization's tax-exempt mission."

But that's not what happened.

Mitt Romney Tax Policy Studies: Candidate Seemingly Contradicts Their Conclusions

WASHINGTON -- Over the past few weeks, the Romney campaign has repeatedly pointed to five separate studies supporting the candidate's contention that a dramatic, across-the-board, reduction in tax rates can be paid for by economic growth and the elimination of deductions and exemptions for high-income earners.

Romney himself referenced these five studies in an interview with Meet the Press on Sunday. His running mate, Rep. Paul Ryan (R-Wis.), said the same during his run through the Sunday show circuit.

Ann Romney: No More Tax Returns Will Be Released

In an interview with NBC set to air Thursday, Ann Romney, wife of Republican presidential candidate Mitt Romney, said her husband's campaign will not release any additional tax returns to the public ahead of the election.

"We have been very transparent to what's legally required of us," Romney told reporter Natalie Morales, according to excerpts from NBC News. "There's going to be no more tax releases given."

Romneys, caught in housing bust, got tax cut in La Jolla

Mitt and Ann Romney were easily able to afford a $12-million La Jolla home.

But that didn't insulate them from the winds buffeting the real estate market in the months following their purchase in 2008.

After paying cash for the Mediterranean-style house with 61 feet of beach frontage, they asked San Diego County for dramatic property tax relief.

Santorum Cashes In on the Very Tax Credit He Claims to Hate

Rick Santorum regularly knocks the stimulus bill that the Democratic Congress passed, and President Obama signed into law, back in early 2009. The American Recovery and Reinvestment Act "cost American jobs," he told CNN last July. But that didn't stop Santorum from claiming a tax credit for home efficiency funded through the stimulus plan that year.

According to his 2009 tax form, which was released last week, Santorum claimed a $3,151 expenditure on new exterior windows and skylights, one of the "qualified energy efficiency improvements" for homes that was granted a tax credit through the stimulus bill. The stimulus bill revived a tax credit that had expired at the end of 2007 and increased the amount of money homeowners could claim. This allowed the Santorum family to knock $945 off their taxes.

The purpose of the tax credit was to help homeowners save money by using less energy, while at the some time generating fewer emissions. But the efficient choices can often cost more upfront—hence the desire to create a tax credit to incentivize that kind of expensive upgrade. The measure was also intended to benefit the manufacturing and construction industries by creating more opportunities for them to make and install the windows and other efficient products.