After eight years in office, Barack Obama will end his presidency on Friday. There has already been much talk of his accomplishments, failures and legacy, but it will take years or even decades for historians, political scientists, journalists and the American people to confidently assess his place among other American presidents.

In the meantime (sorry, we’re impatient), what can we say about how history will judge Obama? Where will future historians rank him compared to his predecessors? One caveat up front: Mount Rushmore aside, history’s judgment isn’t permanent, or even all that stable. Rankings by the public change considerably based on news events. Opinion polls frequently rank John F. Kennedy as the greatest president, but sometimes Abraham Lincoln rises to the top. So, occasionally, does Ronald Reagan. Partisanship and other factors affect public assessments of former presidents, especially recent ones. (Expert rankings are more stable, although even those can shift as time softens partisan wounds.)

But while the public’s rankings may be fickle, it turns out that presidential approval ratings do a reasonably good job of suggesting where presidents rank in the longer term. The chart below shows the ranking of post-World War II presidents by historians and political scientists commissioned by C-SPAN in 2009 along with their final approval rating collected by Gallup (for consistency). There’s a clear, if rough, relationship: The more popular a president when he leaves office, the more highly, on average, he will be rated by historians.

If Obama’s current approval rating of 57 percent holds through Friday, he would rank behind only Bill Clinton, Ronald Reagan, Dwight Eisenhower and John F. Kennedy since World War II. Based on a simple linear model, that rating indicates experts will ultimately rank Obama about 12th among all presidents (the 95 percent confidence interval predicts his rank would fall between 6th and 19th). While naïve, it accords with the rank (15th) afforded him by 238 presidential scholars surveyed by Siena College Research Institute in 2010. Similarly, a 2014 survey of political scientists put him at No. 18.

RANK PRESIDENT 1 Abraham Lincoln 2 George Washington 3 Franklin D. Roosevelt 4 Theodore Roosevelt 5 Harry S. Truman 6 John F. Kennedy 7 Thomas Jefferson 8 Dwight D. Eisenhower 9 Woodrow Wilson 10 Ronald Reagan 11 Lyndon B. Johnson 12 James K. Polk 13 Andrew Jackson 14 James Monroe 15 Bill Clinton 16 William McKinley 17 John Adams 18 George H.W. Bush 19 John Quincy Adams 20 James Madison 21 Grover Cleveland 22 Gerald R. Ford 23 Ulysses S. Grant 24 William Howard Taft 25 Jimmy Carter 26 Calvin Coolidge 27 Richard M. Nixon 28 James A. Garfield 29 Zachary Taylor 30 Benjamin Harrison 31 Martin Van Buren 32 Chester A. Arthur 33 Rutherford B. Hayes 34 Herbert Hoover 35 John Tyler 36 George W. Bush 37 Millard Fillmore 38 Warren G. Harding 39 William Henry Harrison 40 Franklin D. Pierce 41 Andrew Johnson 42 James Buchanan How scholars ranked the presidents in 2009 Source: C-SPAN

While scholars in recent surveys haven’t ranked Obama as highly as public approval ratings right now suggest, in part perhaps because his ratings have risen as his term comes to a close, there are other observations that may push his rank toward the more favorable end of the range. For one thing, Obama is a two-term president, a line on his resume that puts him toward the higher end of the list by itself, as winning a second term is arguably a “prerequisite for presidential greatness.” Winning a second term may make Obama more like Dwight Eisenhower and less like one-term presidents Gerald Ford or George H.W. Bush. Only 14 of 43 presidents have served two terms. Obama remained mostly popular while successfully confronting a serious economic recession, like Franklin Delano Roosevelt, and managing lingering wars like Reagan. While Obama did not enjoy boom times like Clinton’s 1990s, he was also not mired in scandal as Clinton was. Though health care reform, his signature domestic policy, may be repealed in the coming weeks, it has probably already changed the landscape of national health care policy going forward. Moreover, being the first African-American president will keep Obama in the mix of notable presidents, perhaps resembling Kennedy, the first Catholic president.

Historians and political scientists generally identify the great presidents as those who are able to transform government and how Americans view it. They disagree, however, about how much control presidents have over their legacy — whether this power emanates from the personal skills of presidents or the “political time” in which they serve. Columbia University’s Richard Neustadt emphasized individual characteristics and personal political acumen in his seminal book “Presidential Power and the Modern Presidents,” which analyzed presidents from the middle of the 20th century onward. Those from the Neustadt school give credence to a president’s ability to persuade the public, negotiate with government officials and cast a vision. By contrast, Yale University’s Stephen Skowronek has instead argued that the political context in which presidents serve is the key factor shaping the power they can wield and their eventual success — the political environment outweighs individual abilities. For Skowronek, the key distinctions are whether presidents are affiliated with the dominant political regime (e.g., Republicans before the Great Depression or Democrats after it) and whether that political regime is vulnerable (think Herbert Hoover) or resilient (post-New Deal Democrats).

How might scholars from these two camps view Obama’s greatness? Obama, at first, wielded personal political skills well, especially on the campaign trail and within his own party. In 2008, his speeches and rallies captivated much of the nation. But, whether or not it was his fault, he was unable to successfully bargain with the Republican Congress. Legislatively, Obama’s greatest accomplishments, such as the Affordable Care Act and the auto industry bailout, happened without Republican support. And the past six years have been marked by deep partisan conflict. If political greatness is about personal skill to overcome challenges of governing, Obama may not fare well as history ruminates on his legacy.

Understanding a president’s political context takes more time. Some of the greatest presidents — Lincoln, FDR, Reagan and even George Washington — operated in transition periods where the existing political regime was vulnerable. This allowed the president to seize the opportunity and initiate major changes. Skowronek calls this the “Politics of Reconstruction.” Lincoln’s Republican Party moved away from the Democratic Party’s accommodation of slavery. Roosevelt’s New Deal Democrats triumphed over the Republican’s laissez faire economic policy, and Reagan’s small government Republicans pushed back against post-New Deal liberalism. Many of those transitions only became evident in retrospect.

When Obama first took office, some suggested that he too would engage in “reconstruction” politics, transforming America from the small government conservatism that had dominated since Reagan. Facing the worst economic times since the Great Depression, Obama bailed out the auto industry (a process begun by his predecessor), launched a major stimulus package and passed the Affordable Care Act. Unemployment fell, and consumer confidence rose. That sounds like reconstruction, and it might have easily counted as such if Hillary Clinton had been elected to institutionalize those gains. But the election of Donald Trump, along with decisive Republican gains in state and Congressional offices over the past six years, has scholars waiting to see how Obama’s policies will fare. Settling on a way to characterize Obama’s political context is especially challenging when the public is so deeply divided over just what the economic and political realities are.

Despite his many critics, particularly among foreign policy and religious conservatives, there are multiple signs that Obama will be remembered well by history. The next four years, however, will send strong signals about how lasting his achievements will be. Is Trump the blip within the rise of liberal, Democratic presidential politics, or is Obama the exception? Were Obama’s domestic and international policies successful at pushing toward a new era, or were they repudiated? Only time will tell. And Obama’s place in the pantheon of presidents will depend on the answer.