South Dakota ranked 46th in population in the US with an estimated total of 761,063 in 2002, an increase of 0.8% since 2000. Between 1990 and 2000, South Dakota's population grew from 696,004 to 754,844, an increase of 8.5%. The population is projected to reach 810,000 by 2005 and 866,000 by 2025.
In 2000, the median age for South Dakotans was 35.6. In the same year, more than 26.8% of the populace was under the age of 18 while 14.3% were age 65 or older. The population density in 2000 was 9.9 persons per sq mi, making it the 5th most sparsely populated state in the nation.
The leading cities were Sioux Falls, with an estimated 2002 population of 130,491; and Rapid City, with 59,607 residents as of 2000.