Bluebulb Projects' The Measure of Things presents:
25 is about six times the number of Living U.S. Presidents
In other words, the count of Living U.S. Presidents is 0.20 times that amount.
(a.k.a. Presidents of the United States; a.k.a. Presidents of the United States of America; a.k.a. POTUS), (2016 figures) (including current)