Half of Bill and Hillary Clinton’s charitable giving last year went to the Bill, Hillary, and Chelsea Clinton Foundation, according to a review of the latest financial disclosures from their private foundation.

The Clintons earned more than $28 million in 2014 and claimed around $3 million in income as charitable tax deductions, according to tax returns released by Hillary Clinton’s campaign last Friday. The campaign emphasized Clinton’s charitable giving in a press statement, saying that it "represented 10.8 percent" of her income in 2014. But roughly half of that money—$1.8 million—appears to have been channeled to the Bill, Hillary, and Chelsea Clinton Foundation.

According to the tax returns, the Clintons gave $3 million in 2014 to the Clinton Family Foundation, a small private foundation that the family uses as a pass-through to other charities. Records show the CFF disbursed $3.7 million in 2014, including $1.8 million to the Bill, Hillary, and Chelsea Clinton Foundation.

That contribution was the family’s largest by a significant margin that year. They made numerous smaller donations to other groups, including the University of Arkansas, the American Ireland Fund, and the American Friends of the Peres Center.

The $1.8 million contribution is also by far the largest annual donation the Clintons have made to the Bill, Hillary, and Chelsea Clinton Foundation in recent years. In the past five years combined, they gave a total of $1.1 million to the organization. Their last large donation was in 2008, when they gave $1 million.

While the Clintons do not receive direct compensation from the Bill, Hillary, and Chelsea Clinton Foundation, they do benefit from travel, and many of their longtime aides have served on its payroll.

The foundation has come under fire for its unusual structure. Charity Navigator put the Clinton Foundation on its "Watch List" earlier this year because it said the organization did not meet its criteria due to its "atypical business model."

The group is also under review from the Better Business Bureau, after failing to meet its transparency standards in the past.

Clinton’s newly released tax returns, which show that she and her husband have earned $140 million since 2007 could bolster Republican efforts to frame the former secretary of state as a wealthy elitist who is out of touch with average Americans. Vox reported Monday that Clinton has paid more in taxes since 2007—$57.5 million—than GOP presidential candidate Jeb Bush has earned in his entire career spanning back to 1981.

The returns have also opened her up to charges of hypocrisy from critics.

Americans for Tax Reform slammed Clinton on Tuesday for forming an "Article 4 trust," which the group said appears to be a method to avoid paying estate taxes—a tax Clinton has supported.

"Clinton has consistently voted for the Death Tax throughout her time in public office and forcefully condemned attempts to lower it," ATF said in a statement. "But when it comes to her own finances, it is a different story. The newly released tax returns buttress earlier reports outlining the ways Clinton uses financial planning strategies that shield her Death Tax liability."