May 9 (Bloomberg) — Employers in the U.S. posted fewer job openings in March, showing the surge is hiring last month will be difficult to sustain.

The number of positions waiting to be filled fell by 111,000 to 4.01 million in March from a revised 4.13 million the prior month, the Labor Department reported today in Washington. Openings had surged by 251,000 in February, the biggest jump in a year.

The data probably mean the 288,000 payroll increase in April represented pent-up demand after an unusually harsh winter, indicating employment gains are likely to moderate. Today's report contains four of nine measures monitored by Federal Reserve Chair Janet Yellen to help inform monetary-policy discussions.