President Donald Trump has donated $100,000 of his salary to the federal agency that manages research on alcohol and alcohol related issues.

The sizable donation — which was the president’s third quarter salary of 2018 — was given to National Institute on Alcohol Abuse and Alcoholism (NIAAA), the White House revealed. The NIAA “conducts research on the impact of alcohol use on human health and well-being” and serves as “the largest funder of alcohol research in the world,” according to the organization’s website.

The research agency was just the latest recipient of Trump’s presidential salary.

As a 2016 candidate, the billionaire real estate mogul pledged not to accept a salary if elected president. Trump, who by law must be compensated, has followed through on this promise by giving away his $400,000 annual government income to various federal departments every quarter. (RELATED: Report: Trump Said Paul Ryan ‘Screwed Him’ By Not Securing Border Wall Funding Earlier)

Since occupying the White House, Trump has donated to the National Park Service, Department of Transportation, the Department of Veterans Affairs, the Small Business Administration and other agencies. Herbert Hoover and John F. Kennedy are the only other U.S. presidents to refuse a salary while in office.

The most recent donation is a personal issue for the president. Trump’s brother, Fred Trump Jr., died nearly four decades ago at the age of 43 after battling alcohol addiction. The president has said the experience affected his views on alcohol consumption.

Before his passing, Fred Trump would frequently tell Donald Trump to never drink or smoke — a warning the 45th president says he’s followed.

“I’m not a drinker. I can honestly say I’ve never had a beer in my life. OK? It’s one of my only good traits. I don’t drink,” Donald Trump said to the media in October. “Can you imagine if I had? What a mess I would be? I would be the world’s worst.”

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