Bureau of Labor Statistics faces scrutiny over data collection methods following disappointing July jobs report that missed economist estimates by 37,000 positions.

How exactly does the BLS assemble the critical jobs report? And what is the commissioner’s role? Here’s what we know.

While the downward revision of May and June payroll growth by 258,000 marked the largest two-month downward revision to the jobs numbers since 1968, revisions themselves are not uncommon. Revisions are "a feature, not a bug" of the agency's reporting process, Erica Groshen, former BLS commissioner under the Obama administration told CBS MoneyWatch.