Although Latin America was producing bumper coffee crops, military demands on shipping and the prioritization of U.S. military personnel brought about rationing at home. Although sugar rationing had begun in May, coffee wasn’t rationed until November 1942.

For family members older than 15 years, Stamps #19-28 were each designated for one pound of coffee during a specified five-week period. The stamps expired at the end of the period and could not be accumulated.

see: Under His Wings: Make It Do – Coffee Rationing in World War II.