The U.S. Census Bureau estimates that the nation’s population increased from 326.7 million (July 2018) to 328.1 million (July 2019) — adding 1.5 million new residents. On average, the U.S. population has increased about 0.6 percent per year since 2014 or a 3.1 percent change over the past five years.
Idaho had the fastest rate of growth at 2.1 percent over the past year. Rounding out the list of most rapidly growing states are Nevada, Arizona, Utah each at 1.7 percent, Texas and South Carolina at 1.3 percent, Washington and Colorado at 1.2 percent, and Florida at 1.1 percent. Population totals decreased in nine states: Vermont at -0.1 percent, Mississippi, Connecticut, and Louisiana each at -0.2 percent, Hawaii at -0.3 percent, New York and Illinois at -0.4 percent, Alaska at -0.5 percent, and West Virginia at -0.7 percent.
The most populous states in the US are California with 39.5 million, Texas with 28.9 million, Florida with 21.4 million, New York with 19.4 million, Pennsylvania with 12.8 million and Illinois with 12.6 million. States with the largest one-year, July-to-July, population gains were Texas with over 367,200 population increase, Florida with over 233,400 population increase, Arizona with over 120,600 population increase, North Carolina with over 106,400 population increase and Georgia with over 106,200 population increase.
Missouri ranked 18th by population size with 6,137,428 residents. The state gained 15,805 new residents between July 2018 and July 2019. Neighboring Tennessee added 57,543 residents; neighboring Illinois lost 51,250 residents. Tennessee had the largest one-year percentage increases among states that surround Missouri at 0.8 percent. Nebraska grew by 0.5 percent, Oklahoma grew by 0.4 percent, Arkansas and Missouri both grew by 0.3 percent, Iowa grew by 0.2 percent and Kansas grew by 0.1 percent.
For 2019 Missouri counties population St. Louis County had the largest Missouri population with 994,205 residents followed by Jackson County with 703,011 residents, St. Charles County with 402,022 residents, St. Louis City with 300,576 residents, and Greene County with 293,086 residents. The county with the smallest population in Missouri is Worth County with 2,013 residents.
Missouri Counties with the largest one year (2018 to 2019) increase in population include Clay County with 3,588 population growth, St. Charles County with 3,242 population growth, Jackson County with 2,227 population growth, and Greene County with 2,032 population growth. Greatest loss of population between 2018 and 2019 was found in St. Louis City with 2,843 population decline and St. Louis County with 1,014 population decline.