Cuba-US relation once again becomes a news headline. I found an interesting fact about term length for presidency on W|A about the leaders in the two countries.
W|A has a very cool and standard-Instagram-selfie-style portrait for Fidel Castro

Besides the image data, W|A gives a data table about duration of him serving Cuba as a high rank officer

Castro has been the first chair of the Communist Party of Cuba from 1965.
during which time the people in US have had seen 9 presidents. From:

to President Obama. Seriously?! ( just click the "more" button in this link under the "Sequence" session to generate the following table)

You may find more useful information and fun facts with people data domain on Wolfram Alpha plus the build-in people & history data in Wolfram Language