Create bulk gross earnings for W-2 payroll

Adds multiple "gross earning" records in one operation, each consisting of a single earning type, rate, count (or duration), and optionally a unique "external ID" that identifies the earning in your system.

You can provide up to 1000 earnings in the payload of this call. If you need to record more than 1000 earnings, you should call this endpoint multiple times.

This operation is atomic: either all gross earnings will be successfully recorded, or an error will be returned and none of the gross earnings will be recorded.