California is the top region by population in the United States of America. As of 2016, population in California was 39,250.02 thous. of persons that accounts for 12.97 % of the United States of America's population. The top 5 regions (others are Texas, Florida, Illinois, and Pennsylvania) account for 37.43 % of it. The United States of America's total population was estimated at 302,701.05 thous. of persons in 2016.
Intercensal Estimates of the Resident Population. At the national level, the resident population is affected by births, deaths, and net international migration (NIM) only. Pop. Estimate = Base Pop+BerthsDeaths+NIM At the sub-national level (i.e., states and counties), the resident population is affected by an additional component of population change: net internal, or domestic, migration (NDM). Pop. Estimate = Base Pop+BerthsDeaths+NIM+NDM.