By Amy Bickel Kansas Agland

Kansas farmers continue to age while their numbers decline and farm sizes increase, the latest five-year agriculture census shows.

The U.S. Department of Agriculture released the preliminary U.S. Census of Agriculture Thursday. More detailed state-level data will follow in coming months.

Kansas farms totaled 61,733 - down 3,758 from the 2007 census. The average size of the farm, 747 acres, is up by about 6 percent from the previous census - showing the continued trend of fewer, but bigger, farms.

However, only 29,857 of Kansas farm operators say farming is their primary occupation, down by about 1,000 producers.

In 2012, the United States had 2.1 million farms - down 4.3 percent from the previous Census in 2007. In terms of farm size by acres, this continues an overall downward trend in mid-sized farms, while the smallest and largest-size farms held steady.

Other findings:

Age of the farmer: In 2012, the average age of a principal farm operator rose slightly both nationally and in Kansas - to 58 years old. The number of farmers under age 34 was 4,327, nearly unchanged from the last count. The number of farmers ages 35 to 44 declined by about 700 producers. Meanwhile, nearly 50,000 of Kansas' farmers have been on the farm more than 10 years.

Women farmers: The number of women farmers declined by about 1,200, to 6,783. However, the number of minority farmers increased. Farmers claiming an ethnicity of African American rose by 18, to 165. Asian farmers rose from 35 in 2007 to 71 in 2012. Native American farmers rose by 100 to nearly 400 producers.

Kansas ag sales: Kansas ranks in the top 10 for total agricultural sales. That included being in the Top 10 for crop and livestock sales, respectively. Kansas farmland: Kansas had 46.1 million acres of land used for farming operations, about the same as reported five years earlier. Economic class: Kansas farms by economic class of $50,000 or less totaled 40,000 - down about 5,000 farmers from 2007. Meanwhile 2,400 farmers the economic guidelines of more than $1 million - a number that has increased by about 600 farmers since 2007.

Conducted since 1840 by the USDA's Agricultural Statistics Service, the Census of Agriculture accounts for all U.S. farms and ranches and the people who operate them, according to the agency. The Census tells a story of how American agriculture is changing and lays the groundwork for new programs and policies that will invest in rural America.