Sen. Bernie Sanders (I-VT) released a decade’s worth of tax returns on Monday, detailing millions in income—2.26 percent of which he donated to charity.

The documents show that over the years, Sanders’ income ranged from $205,617 to $1.1 million, while his charitable giving ranged from less than 1 percent to just over 4 percent depending on the year.

Last year, Sanders’ total income was $566, 421 and he donated $18,950 or 3.35 percent. In 2017, his income was $1.1 million and he gave away $36,300 or 3.15 percent. The year before that he also made more than $1 million but donated $10,600 or less than 1 percent.

His income peaked in 2016 and 2017 due to sales of his book, Our Revolution.

Based on IRS data, Sanders’ rate of giving was below the average for his income bracket in some years and or at or above in other years.

Sanders had resisted releasing his tax returns during his last run for office, sparking speculation as to what would be in the records that could prove political problematic.

The top line number shows that the Senator is among the millionaire class that he often bemoans. But the charitable giving also presents its own set of political vulnerabilities, which Sanders’ team appeared to acknowledge in a statement on its website explaining that the tax returns do not include proceeds from one of his books, The Speech, “which are donated directly to charity.”

“The Sanders do not take a tax deduction for those contributions, so they do not show up on their tax returns,” the statement read. “The Sanders’ donations have gone primarily to senior centers, low-income organizations, educational entities, and environmental and housing advocacy groups,” the statement said.

Reached for additional comment, Sanders’ campaign spokeswoman Arianna Jones noted that the senator’s policy platform calls for a greater government footprint in areas that are currently struggling to survive on charitable largesse.

“Over the last decade, Bernie and Jane Sanders have donated more than $100,000 to charity. Their overall charitable giving rates have been roughly in line with the average rates in America as a whole,” the statement read.

“In some years, they gave more than 3 or 4 percent of their income to charity. They have given to senior centers, low-income organizations, educational entities, and environmental and housing advocacy groups. They also believe that while voluntary charitable donations are commendable, they can never replace ongoing public investments in major social programs and services that improve people’s lives.”