The number of U.S. jobs posted online rose 0.1% in June month-over-month to 3.8 million, virtually unchanged from May, according to The Conference Board's online help-wanted ad measure. Compared to June 2007, the number of online ads was down 11.2%.

"Employment declines are likely to continue through summer," said Gad Levanon, senior economist at The Conference Board. "Spring is typically a time of seasonal increases in labor demand, but not this year."