Working in janitorial may be considered among the lowest-ranking and obscure positions in existence, but the janitor of the San Francisco Bay Area Rapid Transit (or BART) has been raking in the cash for the past few years by working his butt off.

Simply by working overtime, Liang Zhao Zhang earned $162,050 last year — more than four times his salary of $57,945 — and has earned $235,000 since 2015. That figure is bumped up to $271,243 once other benefits are factored in.

Whenever there was an overtime slot available, Zhang would instantly sign up for it. “He is likely working almost every day of the year cleaning our stations. He is signing up for time that is also available to others—if he doesn’t take them, someone else will,” says BART spokeswoman Alicia Trost.

“It’d be great if all janitors were paid $200k, but I seriously doubt many of BART’s riders—who must pay for this excess—are ever afforded that opportunity,” adds Transparent California research director Robert Fellner.

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