The number of U.S. jobs posted online fell 16.4% year-over-year in April, according to The Conference Board's online help-wanted advertising survey. The number of jobs was also down month-over-month. There were 3.6 million online jobs ads in April, down 2% from March.

"The weakness in online advertised vacancies evident over the last few months deepened in April and hiring is likely to continue to be lackluster into summer," said Gad Levanon, economist at The Conference Board. "April is a month when we normally see employers increasing their recruitment, but this year it actually declined."

Also falling was The Conference Board's consumer confidence index, which dropped to 62.3 in April from 65.9 in March.