For each filing with a wage on record: gap = BLS median wage for the occupation minus the offered wage, floored at 0 (one wage per filing). Certified, denied, and withdrawn filings add their gaps separately.
PERM source files carry no self-reported prevailing wage, so the market reference is the BLS OES median (BLS OES a_median: state median when the worksite state has one, else national; latest available survey year).
The estimate covers 1,538,120 filings that have both a wage and a BLS match. These figures are modeled estimates, not adjudicated findings. Certified, denied, and withdrawn record the application outcome; they do not show whether a job started or a wage was paid.