USPS September Price Change
United States Postal Service (USPS) Price Changes for Priority Mail – Effective September 7, 2014
Commercial Base Price (CBP): Some prices for Priority Mail Letters, Large Envelopes, Parcels and Regional Box C are reduced on average by 0.9 percent
Retail: Some Priority Mail Retail prices have a modest increase; an average of 1.7 percent.
This does not effect the osCommerce USPS Module.
Full details here.