Quote of the Day

Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.

— Albert Einstein

While crawling around the Wikipedia looking for presidential information, I found a list of the ages at inauguration of the US presidents ordered from oldest to youngest. I threw Hillary Clinton and Donald Trump into the list (Table 1) to see where they would place – they are old by historic standards. In fact, Donald Trump would be the oldest ever.

As a check, I computed the inaugural ages of all the presidents using Excel and found that the Wikipedia was accurate, which I normally find true. The age calculation was complicated by the fact that the age system used in Excel does not work for ages before 1900. Fortunately, I found the excellent extended date add-in from Walkenbach, which allows you to work with the string representation of dates. For those of you who like to code, Excel's VBA does not have the same date restrictions as its workbooks, so you can write your own macros that will work quite well.

Before I dive into the specifics of presidential ages at inauguration, let's look at a histogram of the inauguration ages of all the presidents (Figure 2). Observe that most presidents are between 50 and 60 years old.

Table 1 shows the age of all the presidents by their age in years and days, plus the ages of Hillary and Donald.

President/Candidate |
Age at inauguration |
---|---|

Donald Trump | 70 years, 220 days |

Ronald Reagan | 69 years, 349 days |

Hillary Clinton | 69 years, 86 days |

William Henry Harrison | 68 years, 23 days |

James Buchanan | 65 years, 315 days |

George H. W. Bush | 64 years, 222 days |

Zachary Taylor | 64 years, 100 days |

Dwight D. Eisenhower | 62 years, 98 days |

Andrew Jackson | 61 years, 354 days |

John Adams | 61 years, 125 days |

Gerald Ford | 61 years, 26 days |

Harry S. Truman | 60 years, 339 days |

Grover Cleveland (2nd Inauguration) | 59 years, 351 days |

James Monroe | 58 years, 310 days |

James Madison | 57 years, 353 days |

Thomas Jefferson | 57 years, 325 days |

John Quincy Adams | 57 years, 236 days |

George Washington | 57 years, 67 days |

Andrew Johnson | 56 years, 107 days |

Woodrow Wilson | 56 years, 66 days |

Richard Nixon | 56 years, 11 days |

Benjamin Harrison | 55 years, 196 days |

Warren G. Harding | 55 years, 122 days |

Lyndon B. Johnson | 55 years, 87 days |

Herbert Hoover | 54 years, 206 days |

George W. Bush | 54 years, 198 days |

Rutherford B. Hayes | 54 years, 151 days |

Martin Van Buren | 54 years, 89 days |

William McKinley | 54 years, 34 days |

Jimmy Carter | 52 years, 111 days |

Abraham Lincoln | 52 years, 20 days |

Chester A. Arthur | 51 years, 349 days |

William Howard Taft | 51 years, 170 days |

Franklin D. Roosevelt | 51 years, 33 days |

Calvin Coolidge | 51 years, 29 days |

John Tyler | 51 years, 6 days |

Millard Fillmore | 50 years, 183 days |

James K. Polk | 49 years, 122 days |

James A. Garfield | 49 years, 105 days |

Franklin Pierce | 48 years, 101 days |

Grover Cleveland (1st Inauguration) | 47 years, 351 days |

Barack Obama | 47 years, 169 days |

Ulysses S. Grant | 46 years, 311 days |

Bill Clinton | 46 years, 154 days |

John F. Kennedy | 43 years, 236 days |

Theodore Roosevelt | 42 years, 322 days |

It is a kind of interesting thing that when you compare the age of the president at his/her inauguration and compare that to their life expectancy we find that starting from president Ford the ratio inauguration age/life expectancy is going below 1. Election of either Trump or Clinton will bring it back above 1

That is interesting. I will add that to my spreadsheet. Thanks.

mark

How is this possible? Life expectancy in the Unites States is ~79 years. Clinton or Trump age/life would both be <1..?

You're saying that on average; presidents are inaugurated at a time past their life expectancy? That doesn't seem right.

The page you are commenting on is about the age of the presidents on their day of inauguration. No probabilities are involved here. There is another post here where I discuss the probability that a 70 year old man would finish an 2 - 4 year terms. Based on Social Security longevity data, 23% of 70 year-old males do not make it 78. That is all I am saying.

mark

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