The Count of Things

Bluebulb Projects' The Measure of Things presents:

It's about one-fourth the number of Wolves in Yellowstone National Park

In other words, 25 is 0.240 times the count of Wolves in Yellowstone National Park, and the count of Wolves in Yellowstone National Park is 4.170 times that amount.

(a.k.a. Henihco'oo; a.k.a. Héetíhco'oo) (December 2014 figures; Wyoming Park area)

It's about one-fifth the number of Elements on the Periodic Table

In other words, 25 is 0.2120 times the count of Elements on the Periodic Table, and the count of Elements on the Periodic Table is 4.720 times that amount.

(a.k.a. Periodic Table of the Elements, a.k.a chemical elements) (confirmed elements as of 2016)

It's about one-fifth the number of Union Stations in the United States

In other words, 25 is 0.1850 times the count of Union Stations in the United States, and the count of Union Stations in the United States is 5.410 times that amount.

(a.k.a. Union Terminal; a.k.a. Joint Station; a.k.a. Union Depot) (2016 figures)

It's about one-fifth the number of Moons in our Solar System

In other words, 25 is 0.1710 times the count of Moons in our Solar System, and the count of Moons in our Solar System is 5.850 times that amount.

(2015 figures) (confirmed moons only; dwarf planet satellites not included)

It's about six times the number of Living U.S. Presidents

In other words, the count of Living U.S. Presidents is 0.20 times 25.

(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)
As of this writing, there are five living United States Presidents — President Carter, President Clinton, President Obama, and the second President Bush. At no point in U.S. history have their been more than six (6) living presidents, this circumstance having occurred three times.

It's about one-tenth the number of John Wayne films

In other words, 25 is 0.140 times the count of John Wayne films, and the count of John Wayne films is 7.140 times that amount.

(a.k.a. "Duke", a.k.a. JW, a.k.a. Marion Mitchell Morrison, a.k.a. Marion Robert Morrison, a.k.a. Duke Morrison) (films starring the actor in any size role)

It's about one-tenth the number of Bones in the Human Body

In other words, 25 is 0.1210 times the count of Bones in the Human Body, and the count of Bones in the Human Body is 8.260 times that amount.

(adult, excluding sesamoid bones and ossicles)