It's about 100 times the number of Moons in our Solar System.
In other words, 18,000 is 123 times the count of Moons in our Solar System, and the count of Moons in our Solar System is 0.00813 times that amount.(2015 figures) (confirmed moons only; dwarf planet satellites not included)
Astronomers and other scientists have confirmed the presence of 146 moons orbiting the major planets of our Solar System. About one third of those moons — 53 — are in orbit around the planet Saturn
It's about 150 times the number of Union Stations in the United States.
In other words, 18,000 is 133 times the count of Union Stations in the United States, and the count of Union Stations in the United States is 0.00752 times that amount.(a.k.a. Union Terminal; a.k.a. Joint Station; a.k.a. Union Depot) (2016 figures)
Typically shared between multiple railroad companies and stations, there are about 135 "Union Stations" in the United States. Of these, the busiest station is Chicago Union Station, which handles 120,000 passengers each year.
It's about 150 times the number of Elements on the Periodic Table.
In other words, 18,000 is 153 times the count of Elements on the Periodic Table, and the count of Elements on the Periodic Table is 0.00654 times that amount.(a.k.a. Periodic Table of the Elements, a.k.a chemical elements) (confirmed elements as of 2016)
From element number one, hydrogen, to element one-hundred eighteen, ununoctium, there are 118 confirmed elements on the Periodic Table. Ninety-four of the elements exist in nature, and the remaining twenty-four have only been synthesized in labs (not having occurred naturally in the time since scientists have begun researching them)
It's about one-one-hundred-fiftieth the number of ATMs in the World.
In other words, the count of ATMs in the World is 200 times 18,000.(2015 figures) (approximate)
There are approximately 3 million ATMs in the world, including sites in Antarctica, cruise ships, US Navy ships, and Tibet. ATM's typically hold between $20,000 and $100,000, depending on the size of the crowds where they're located.
It's about 150 times the number of Wolves in Yellowstone National Park.
In other words, 18,000 is 173 times the count of Wolves in Yellowstone National Park, and the count of Wolves in Yellowstone National Park is 0.00578 times that amount.(a.k.a. Henihco'oo; a.k.a. Héetíhco'oo) (December 2014 figures; Wyoming Park area)
As of the 2014 population count, there were 104 wolves living in Yellowstone National Park, in twelve packs. All of the wolves now living in the Park are thought to have descended from the 66 wolves (re)introduced into the Park in 1995-96.
It's about 200 times the number of Keys on a Piano.
It's about 250 times the number of Submarines in the US Navy.