The president of the United States is now paid $400,000 a year. Unlike members of Congress, the president does not get an automatic pay raise or cost-of-living adjustment every year.

The president's salary is set by Congress, and lawmakers have seen fit to raise the pay for the most powerful position in the world precisely five times since George Washington became the nation's first president in 1789.

The most recent salary hike was effective in 2001 when President George W. Bush became the first commander-in-chief to make the $400,000 salary—double the amount his predecessor, President Bill Clinton, was paid a year.

Presidents don't have the power to raise their own salaries. In fact, this point is specifically covered in the U.S. Constitution which states that:

"The President shall, at stated times receive for his services, a compensation, which shall neither be increased nor diminished during the period for which he shall have been elected ..."

Washington tried to decline his presidential salary, but since it is required by the Constitution he accepted it. Likewise, President Donald Trump pledged to work without a salary, but since he was legally required to accept it has instead given the quarterly pay back to various government agencies since he has been in office.

Here's a look at presidential salaries through the years, a list of which presidents were paid how much, starting with the current rate of pay.