Women accounted for almost all of job gains in August. Here's why

There's a group to thank for August's blockbuster jobs report : women.

Women accounted for 158,000 — or around 98% — of the 162,000 jobs added in the month, according to a CNBC analysis of data released Friday by the Bureau of Labor Statistics.

Men represent the remaining 4,000 net positions added, meaning their contribution to overall payroll growth was nearly 40 times smaller.

The Economic Security Project, a progressive nonprofit, first pointed out the anomaly in Friday's data.

With Friday's report, the gap between the number of jobs held by women compared with men climbed to levels never before seen, according to Laura Ullrich, director of economic research at the Indeed Hiring Lab.

"We are in the midst of a shift," Ullrich said. "It is changing right before our eyes."

Friday's report offers the latest signal of how much momentum women are gaining in an otherwise lackluster job market.

Compared with 12 months ago, the BLS found that the level of employed women has grown by more than 870,000 on a seasonally adjusted basis. The male gender has lost nearly 1.5 million employed workers over the same timeframe.