At 72.3 million, the number of children recorded in the 2000 Census was the largest in the country’s history -- even larger than during the height of the post-World War II baby boom. There was a substantial increase in the number of children during the 1990's, as the under-18 population grew 8.7 million over the decade. In the 20th century, the 1950's was the only decade that saw a bigger numerical increase than the 1990's. Minority children accounted for 98 percent of the growth in the child population during the 1990's. Only 200,000 of the 8.7 million children added to the population between 1990 and 2000 were non-Hispanic White children. State-level changes in the number of children ranged from a 72 percent increase in Nevada to a 9 percent decrease in West Virginia. Besides West Virginia, four other States and the District of Columbia also saw a decrease in the number of children over the decade. Racial diversity among children is increasing at a fast pace. Minority children (any group other than non-Hispanic White) accounted for 39 percent of the population under 18 in 2000, compared with 31 percent in 1990. Racial and Hispanic minorities account for a significantly larger share of children than of adults. In 2000, about 39 percent of children were minorities, compared with 28 percent of adults. 1 figure, 8 tables, 14 endnotes, appendix