Allan Lichtman says he can predict the outcome of any U.S. presidential election. He often does it months or even years ahead of time. Oh, and his predictions have been right in every presidential election since 1984.

But Lichtman, a distinguished professor of history at American University, doesn’t use polling, demographics or sophisticated analysis of swing states. He makes his predictions based on 13 true/false statements that he says indicate whether the incumbent party will retain the White House or lose it in a given election.

Lichtman and Russian scientist Volodia Keilis-Borok came up with the keys — a series of true/false statements — in the early 1980s. The idea is that if more than half of the keys are true, the incumbent party will stay in power, and if more than half are false, the challenging party will win the White House.

The keys, which are explained in depth in Lichtman’s book “Predicting the Next President: The Keys to the White House 2016” are:

1. Party Mandate: After the midterm elections, the incumbent party holds more seats in the U.S. House of Representatives than after the previous midterm elections.
2. Contest: There is no serious contest for the incumbent party nomination.
3. Incumbency: The incumbent party candidate is the sitting president.
4. Third party: There is no significant third party or independent campaign.
5. Short-term economy: The economy is not in recession during the election campaign.
6. Long-term economy: Real per-capita economic growth during the term equals or exceeds mean growth during the previous two terms.
7. Policy change: The incumbent administration effects major changes in national policy.
8. Social unrest: There is no sustained social unrest during the term.
9. Scandal: The incumbent administration is untainted by major scandal.
10. Foreign/military failure: The incumbent administration suffers no major failure in foreign or military affairs.
11. Foreign/military success: The incumbent administration achieves a major success in foreign or military affairs.
12. Incumbent charisma: The incumbent party candidate is charismatic or a national hero.
13. Challenger charisma: The challenging party candidate is not charismatic or a national hero.