U.S. Secretary of State John Kerry has been the least effective person to hold that post in the past 50 years, according to results of Foreign Policy’s Ivory Tower survey, a poll of 660 U.S. international relations scholars released Thursday. Only two said Kerry was the most effective secretary of state.

The survey didn’t have scholars give explanations for their rankings, which had former U.S. Secretary of State Henry Kissinger as the most effective secretary of state of the past five decades. More than 32 percent of the surveyed scholars, or 213 of them, gave Kissinger that distinction. Nearly 20 percent, or 120 scholars, said they couldn't name the most effective secretary of state.

Secretary of state since 2013, Kerry has had a lot on his plate as the country’s top diplomat. Since he replaced Hillary Clinton, Kerry has had to deal with the crisis in Ukraine, the rise of the Islamic State militant group, last year’s war between Israel and Gaza, and negotiations on Iran’s nuclear program. Clinton was dubbed the most effective secretary of state by 58 scholars, or nearly 8.8 percent.

To put Kerry’s ranking into perspective, he was tied with Lawrence Eagleburger, who held the post for only six weeks during the George H.W. Bush administration, the Washington Post noted. But the Ivory Tower survey lists Kerry last.

Besides ranking the secretaries of state, the poll also sought the opinions of more than 1,600 scholars on the most important foreign policy issues facing the U.S. today and over the next 10 years. Global climate change topped both lists, while armed conflict in the Middle East was second for today’s challenges and third among issues over the next 10 years. Failed or failing states was ranked as the third-biggest challenge facing America today while China’s rising military power was the second-biggest concern in the next 10 years.