NEW YORK — In a troubling snapshot of the declining finances of Americans, considerably more school-age children are living in poverty than in the pre-recession year of 2007, the US Census Bureau reported Tuesday.

Of all 3,142 counties in the US, 653 counties saw significant increases in poverty for children ages 5 to 17, according to the 2010 Census Bureau survey. Only eight counties saw a decrease. Nationally, 19.8 percent of schoolchildren qualify as poor – and one-third of all counties now have child poverty rates above that threshold. About one quarter had child poverty rates significantly lower than the national average.

Among counties with at least 100,000 people, the highest child poverty rates were in Texas’ Cameron County (44.9 percent) and Hidalgo County (44.6), Bronx County in New York (41 percent), Webb County in Texas (38.9), and Missouri’s St. Louis County (38.6). Among all counties no matter their size, Georgia’s Burke County (pop. 23,367) had the highest share of children in poverty, at 47.7 percent.

The Census information has important uses. The Department of Education uses the data in its formula for allocating more than $14 billion a year in federal funds, of which a significant amount is directed to school districts […]