The private sector added only 158,000 jobs in March, ADP announced Wednesday -- lower than the 205,000 Bloomberg News consensus estimate.

However, February’s private sector job total increase was revised higher to 215,000 jobs from the initial estimated 198,000-job gain.

Institutional investors use the private ADP employment figure as a rough gauge of the private sector’s employment status, but economists caution that the report is not strongly correlated with the more-telling U.S. Non-Farm Payroll Report, which includes both private sector and public sector jobs. That report, for March, will be released on Friday at 8:30 a.m. EDT by the U.S. Labor Department.

What's more, for the past three months the private sector has added an average of 191,000 jobs per month -- a strong growth rate, but one that will have to increase further to make up for the more than 9 million jobs lost during the Great Recession to lower the nation's high 7.7 percent unemployment rate, most economists say.