The average age of principal farm operators in the U.S. has increased steadily over the past 30 years, with one of the largest jumps on record occurring between 2002 and 2007 (from 55.3 to 57.1 years of age).
Source: USDA-NASS (2009). 2007 Census of Agriculture: Demographics. http://www.agcensus.usda.gov/Publications/2007/Online_Highlights/Fact_Sheets/demographics.pdf, United States Department of Agriculture: 4 pp.
Simple figures and maps show the disturbing (and a few encouraging) trends in farmer demographics, which highlight the need for new farmers.