Population Trends in 2018: Youngest Kids and New Adults

In the Unit­ed States, the num­ber of kids under the age of 1 fell by near­ly 46,000 chil­dren from 2017 to 2018. The age group’s pop­u­la­tion count — which dipped to 3.9 mil­lion kids in 2018 — has been on the decline since 2015.

State-lev­el sta­tis­tics for America’s youngest kids echo the nation­al data: From 2017 to 2018, every state but one report­ed hav­ing few­er chil­dren under the age of 1. The lone excep­tion — Ida­ho — gained only 40 kids under the age of 1 dur­ing this time frame, accord­ing to the U.S. Cen­sus Bureau’s pop­u­la­tion division.

The trend revers­es — just slight­ly — for America’s newest adults. The num­ber of 18-year-olds increased from 4.2 mil­lion in 2017 to 4.3 mil­lion in 2018, accord­ing to nation­al data.

At the local lev­el, five states — Con­necti­cut, Hawaii, Maine, New Hamp­shire and Rhode Island — saw their total num­ber of 18-year-olds decline from 2017 to 2018. This dif­fer­ence was great­est — yet still mar­gin­al — in Con­necti­cut, which report­ed 217 few­er 18-year-olds in 2018.

The total num­ber of chil­dren (ages birth through 17) in the Unit­ed States sur­passed the 70-mil­lion mark in 1996 before peak­ing at 74.1 mil­lion in 2009. As of 2018 — the most recent full year of data on record — America’s child pop­u­la­tion count had dipped just below 73.4 mil­lion.