Billionaire presidential candidate Tom Steyer has released 9 years’ worth of tax returns

Steyer made $1.2 billion in the past decade and paid over $400 million in taxes.

Billionaire financier Tom Steyer released nine years of tax returns on Thursday afternoon. At over 2,600 pages, the staggering sum of documents is far beyond what any other candidate in the race has reported in tax returns so far.

Steyer made around $1.2 billion from 2009 to 2017, the years his campaign made available. In 2017, Steyer made $146 million. His lowest income was in 2009, when he made $60.8 million.

The long-shot candidate's total taxes over nine years came to $405 million, including about $261 million in federal taxes and $143 million in state taxes. The total effective tax rate -- total taxes divided by adjusted gross income -- was around 34% on average.

Steyer and his wife also donated $190 million to charity, which combines both his personal contributions and his charitable organizations’ contributions.

The tax releases also demonstrate Steyer’s increased political involvement over the years.

In 2009, he gave more than $52,000 in political contributions, but in 2016, the most-recent presidential election, that contribution swelled to $139.6 million. In 2017, his contributions notably sank to $65.4 million.

Steyer has yet to release his 2018 tax returns, which his campaign said he’s still in the process of filing, and which could provide significant insight into what his contributions looked like during the midterm elections when Democrats took back control of the House of Representatives.

According to his campaign, Steyer’s political activities from 2009 to 2017 totaled $365.6 million, including contributions to federal and state candidates; federal and state committees; and to his nonprofit spending for NextGen and Need to Impeach.

Other candidates’ tax returns have shown increasing amounts of wealth throughout the course of their careers, including millionaire status for candidates like former Vice President Joe Biden, and Sens. Bernie Sanders, of Vermont, Elizabeth Warren, of Massachusetts, and Kamala Harris, of California.

As for Steyer, his highest incomes came in 2014 at around $189.3 million and in 2010 at around $175.4 million -- was also the year he and his wife signed the Giving Pledge.

In 2012, the final year he spent as head of his hedge fund, Farallon Capital Investments, he and his wife earned $174.3 million. There is some spike in charitable donations right after 2012, which was right after he stepped down from Farallon. His campaign has said that this was because he wanted to set up several nonprofit/private charities right away: TomKat Foundation, TomKat Ranch and Beneficial State Foundation.

After running Farallon for 26 years, Steyer stepped down to focus on politics and the environment. He launched his nonprofit, NextGen America, which focuses on clean energy, and later, Need to Impeach, which is aimed directly at lobbying for President Donald Trump’s impeachment.

He has poured hundreds of millions of his own money into electing Democrats who support Trump's impeachment. In 2018, through those two political organizations, he spent $74 million in the midterm elections with the goal of electing progressive candidates across the country.

Since throwing his hat into the 2020 ring, Steyer has also stepped down from his outside political ventures. But he has pledged to commit the $50 million he promised for Need to Impeach this year.

Steyer has sparked a good deal of controversy about his past ventures. Some have cited hypocrisy for how he built his fortune with Farallon's deep investment in fossil fuels. But the candidate signed a pledge not to accept money from the fossil fuels industry earlier this year and told "This Week" on July 14 he has changed course on the topic and has spent millions fighting climate change.

"In our business, we invested in every part of the economy, including fossil fuels," he told ABC News' Jonathan Karl. "When I realized what a threat this was, I changed. I divested from all that stuff."

Several of his fellow 2020 candidates on the progressive side have also criticized his wealth -- and the way he’s used it -- promising to pour $100 million of his own money into campaigning, including blanketing the airwaves with advertising.

Warren used his announcement as a springboard for her own fundraising, saying candidates need to be able to do more than just write "big checks." Sanders told MSNBC that he is "tired of seeing billionaires trying to buy political power."

Steyer, who supports a wealth tax, said under his own proposal he would "pay more than an additional $10 million annually in taxes," according to a memo released with the tax returns. Steyer’s wealth tax would require 1 cent for every dollar over $20 million. By comparison, Warren’s wealth tax calls for 2 cents on every dollar after $50 million and 3 cents after $1 billion.

The vast dump of tax documents Thursday afternoon is his campaign’s effort to appear totally transparent and set himself apart from the current White House occupant. Trump's tax returns remain shrouded in mystery.

"This level of financial disclosure is unparalleled for a presidential candidate," campaign manager Heather Hargreaves said in a statement. "Tom is releasing his tax returns now because he believes in providing transparency at all levels of government which includes elected officials. The documents he is releasing also provide voters with an understanding of his role in the private sector, which he has since left behind seven years ago to work for the public good."

Steyer’s personal financial disclosure documents were not included in the document release. His campaign tells ABC News they are currently under review with the Office of Government Ethics and will be released as soon as they have been certified.