Sen. Bernie Sanders on Monday released 10 years' worth of tax returns.

Sanders and his wife, Jane, earned roughly $1.7 million over the past two years, according to their returns.

Sanders had faced a lot of pressure to make his returns public and for weeks did not offer a timeline on when they'd be published.

A number of other 2020 Democrats have also publicly shared their returns.

President Donald Trump has been criticized since 2016 for not publishing his returns and still has not done so.

Shortly after releasing his returns on Monday, Sanders took part in a Fox News town hall and called on Trump to release his returns. "The president watches your network a little bit, right? Hey President Trump, my wife and I just released 10 years (of tax returns) please do the same," Sanders said.

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Sen. Bernie Sanders on Monday released 10 years' worth of tax returns, making good on a pledge he made more than a month ago.

"These tax returns show that our family has been fortunate," Sanders said in a statement. "I am very grateful for that, as I grew up in a family that lived paycheck to paycheck and I know the stress of economic insecurity. That is why I strive every day to ensure every American has the basic necessities of life, including a livable wage, decent housing, health care and retirement security."

He added: "I consider paying more in taxes as my income rose to be both an obligation and an investment in our country. I will continue to fight to make our tax system more progressive so that our country has the resources to guarantee the American Dream to all people."

Sanders and his wife, Jane, earned about $1.7 million over the past two years, according to their returns.

The returns show that Sanders' financial circumstances changed significantly after his 2016 presidential campaign, which catapulted him from being a relatively obscure member of Congress to one of the most recognized figures in US politics.

Here is Sanders' adjusted gross income over the past decade:

2009 : $314,742

: $314,742 2010 : $321,596

: $321,596 2011 : $324,870

: $324,870 2012 : $280,954

: $280,954 2013: $278,799

$278,799 2014 : $205,271

: $205,271 2015 : $240,622

: $240,622 2016 : $1,062,626

: $1,062,626 2017 : $1,131,925

: $1,131,925 2018: $561,293

The Vermont senator had faced mounting pressure to release his returns after he was criticized for not being more transparent about his finances during the 2016 campaign season.

For weeks, Sanders repeatedly did not offer a specific timeline on when he would release his returns, but last week said he would finally make them public by Tax Day, or April 15.

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Meanwhile, after recently acknowledging that he's a millionaire because of profits from book sales, some conservatives, among others, have accused Sanders of hypocrisy in relation to his anti-capitalism rhetoric. The senator has for years decried "millionaires and billionaires" but now finds himself in their company.

The senator dismissed criticism at a recent campaign stop, telling a crowd in Gary, Indiana, he didn't know "it was a crime to write a good book, which turned out to be a best seller."

Sanders said he would not apologize for writing a best-selling book but maintained he still hopes to see a "progressive tax system which demands that the wealthiest people in this country finally start paying their fair share in taxes."

In 2017, Sanders made more than $1 million, largely because of book sales, according to Senate financial disclosures.

The issue of tax returns has become a way for Democratic candidates to take jabs at President Donald Trump, who has repeatedly refused to publish his.

Trump has broken roughly four decades of precedent by declining to make his returns public, and he's embroiled in a fight with congressional Democrats who want to obtain them.

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A number of 2020 Democratic candidates have not yet released their returns but have signaled they plan to do so.

Sen. Kamala Harris released 15 years of returns on Sunday, the longest tax record made public by any 2020 Democrat.

About 30 minutes before Sanders released his tax returns, he took the opportunity to go after Trump's tax policies, tweeting, "Let's remember that Trump's tax policies will raise taxes on millions of working people, while giving $4 billion in tax rebates to Fortune 500 companies and continuing to allow profitable companies like Amazon and Chevron to pay zero in federal income taxes."

Shortly after Sanders' returns were published on Monday, he took part in a Fox News town hall and called on Trump to release his returns. "The president watches your network a little bit, right? Hey President Trump, my wife and I just released 10 years (of tax returns) please do the same," Sanders said.