The September 7, 2014 rate change includes price reductions for Priority Mail when you use a mailing system (like FP’s PostBase with MailOne 2.0) that produces shipping labels with USPS electronic Intelligent Mail Package Barcode (IMPB).
The January 26, 2014 USPS rate change introduced increases for most mail classes. One bright spot was a $0.01 lower price for metered 1-ounce first class letters.
On January 27, 2013 the USPS increased rates in most mail classes and products. One-ounce letters increased from $0.45 to $0.46.