The Friday File: In an effort to lick billions in losses, the USPS plans to halt Saturday delivery of letters in 8/13. Mail volume has plummeted from 210 billion pieces in 2008 to just 160 billion in 2012, a decline of 24% while revenues have declined 13%. Worse, per capita use has declined a whopping 33% as the population grows and kids have no idea what stamps are for.