From the BLS: Job Openings and Labor Turnover Summary

The number of job openings was little changed at 5.8 million on the last business day of April, the U.S. Bureau of Labor Statistics reported today. Hires edged down to 5.1 million while separations were little changed at 5.0 million. Within separations, the quits rate was 2.0 percent, and the layoffs and discharges rate was 1.1 percent. …

The number of quits was little changed in April at 2.9 million.
emphasis added

The following graph shows job openings (yellow line), hires (dark blue), Layoff, Discharges and other (red column), and Quits (light blue column) from the JOLTS.

This series started in December 2000.

Note: The difference between JOLTS hires and separations is similar to the CES (payroll survey) net jobs headline numbers. This report is for April, the most recent employment report was for May.

Job Openings and Labor Turnover Survey Click on graph for larger image.

Note that hires (dark blue) and total separations (red and light blue columns stacked) are pretty close each month. This is a measure of labor market turnover.  When the blue line is above the two stacked columns, the economy is adding net jobs – when it is below the columns, the economy is losing jobs.

Jobs openings increased in April to 5.788 million from 5.670 million in March.

The number of job openings (yellow) are up 4% year-over-year compared to April 2015.

Quits are up 9% year-over-year. These are voluntary separations. (see light blue columns at bottom of graph for trend for “quits”).

This is another strong report, and job openings were tied with the record high set in July 2015.