Unfading chance to be president

In honor of Presidents' Day it is worth exploring the timeline of our leaders, from founding father George Washington, through the current #45 Trump.  There are many interesting statistics one can learn about the lifespan of our great leaders, for example the average year among the lives of the U.S. Presidents is 1878, though we can see #32 Roosevelt onwards were born after this date.  We'll also see something motivating further below concerning the trend in presidents assuming office at earlier ages and not living as long afterwards, until the most recent dozen from about #34 Eisenhower onwards where life expectancies have ascended past the initial 18th century presidents.  The more recent presidents have both maintained long lives (6 including the current president are living) and have equally had the opportunity to assume office at varied ages through that life, illustrating that many paths to eminent distinction are possible in America.

 

We see in the chart above that at any given time, there are nearly 9 presidents (or former presidents) alive.  A careful eye would notice that among the current 6 presidents alive, there are two combinations of presidents born in the same year.  #42 Clinton, #43 Bush and #45 Trump were both born in 1946.  And #39 Carter and #41 Bush were both born in 1924!  As a probabilist (here, and in Statistics Topics) it suffices to say just the chance of only one pair of living presidents to share the same age is 15%.  Make the requirement two combinations such as this out of 6 living presidents and the probability  nose-dives below 1%.

For the 6 living presidents a conditional actuarial life expectancy was estimated to them, beyond todays date.  The mathematics for that are shown through the blog (here, here, here, here, here).  For example, we expect #44 Obama (only age 55 today) to endure to the most into the future, though we expect #39 Carter and #41 Bush to live longer than any other of the 45 presidents (yet just a few additional years).  While the health care afforded to recent presidents is top rate, there are also hazardous risks associated with being president, as noted further below.

The duration of life has nonetheless increased through the top ½ of the presidents’ ranks, from a prior trend towards shorter lives.

 

Next we look at how the age of assuming office plays a conditional role in life expectancy.  See the chart below, where the title is self-explanatory.  We separate the 45 presidents into quartiles based upon their number rank.  Well notice that the average age a president assumed (his first term) was age 56.  Yet in the top 1/2 of the presidents’ ranks (#23 Harrison onwards), we see that the two youngest presidents were #26 Roosevelt at age 42 and #35 Kennedy at age 43.  We also see that the average age of the top dozen presidents assumed office at an average age of 57 (without rounding this comes to ~2 years above average).  And let’s not forget that our newly tenured president is the oldest to assume office, at aged 70.

 

8 presidents have had their life ended while in office, from the pneumonia of #9 Harrison to the assassination of #35 Kennedy.  It is interesting to see that there is otherwise not a clear relationship throughout time, between the age one undertakes presidency, and how long they live afterwards.  And that analysis doesn’t get impacted based on the duration of one’s presidential term(s).