USPS Admits FSS Is Losing Money: On the same day it very publicly announced the planned cessation of most Saturday delivery, USPS released data confirming what Dead Tree Edition speculated about two weeks ago. ( See So Far, FSS Is A Step Backward, USPS Data Indicate. ) The data show that two of the three major types of mail processed on FSS machines—Standard (non-carrier-route) Flats and Periodicals—had experienced larger increases in processing costs the past two years than they had gained in delivery savings.