President Barack Obama has spent more time traveling abroad than other U.S. president in history at this point in their presidencies, according to a forthcoming study from the National Taxpayer Union Foundation (NTUF) provided exclusively to Breitbart News ahead of its public release.

“The most internationally well-traveled President, through five years, is also flying the most expensive-to-operate Air Force One to date,” NTUF wrote.

After five years in the White House, Obama has taken 31 trips for a total of 119 days abroad. At that point in George W. Bush’s presidency, Bush had taken 28 trips for 116 days, while Bill Clinton had taken 27 trips for 113 days. Ronald Reagan, after five years, had taken 14 trips for 73 days while Richard Nixon had taken 12 trips for 60 days after five years in the White House and Lyndon Johnson took 10 trips for 34 days at the half-decade mark. Dwight Eisenhower took 8 trips for 31 days after five years in the White House.

Citing a recent report in the Washington Examiner that found through the Freedom of Information Act (FOIA) that taxpayers are on the hook for about $228,288 per Air Force One flight hour in 2013, a 27 percent increase from the previously confirmed cost of $179,750 per fight hour that NTUF used in its last study, the taxpayer watchdog concludes that Obama’s flights have cost taxpayers more than any other president.

“Taken on its own, the $48,535 jump may not sound all that significant,” NTUF added about the cost increase for Air Force One. “However, when trips are many thousands of miles and span several time zones and continents, the difference can quickly add up.”

NTUF estimates that Obama’s trip to Europe and the Middle East “will likely involve about 29 hours of total travel time, assuming a cruising speed of 575 mph between Washington, Amsterdam, Brussels, Rome, and Riyadh, and then back to D.C.” That amount, the group says, is going to cost taxpayers millions of dollars.

“Using the previous estimate, the total cost of flying Air Force One between those international cities would be about $5,212,750,” NTUF wrote. “Using the new data, the cost comes out to $6,620,352.”

NTUF added that those amounts are just estimates, and the actual cost is likely to be higher. “While these figures are approximations, and do not account for the additional (and likely greater) expenses of transporting the President’s Secret Service and diplomatic entourage, backup aircraft, land vehicles, and advance security teams, it goes to show that higher Air Force One operational costs substantially change the budgetary magnitude of these trips,” NTUF wrote.