You can see the new rates in Notice 123, always good to bookmark:
http://pe.usps.gov/text/dmm300/Notice123.htm#1118064

First rate reduction in 97 years for PO. Those who bought forever stamps, lost some for now.

WASHINGTON (AP) — The cost of mailing a letter is going down.

Beginning Sunday, the price of a first-class stamp drops two cents, to 47 cents. The reduction is the result of an expiring surcharge that had been put in place in January 2014 to help the beleaguered Postal Service recoup $4.6 billion in losses dating back to the Great Recession.

Postmaster General Megan J. Brennan says the forced rate reduction would exacerbate Postal Service losses. The agency estimates it would lose $2 billion in annual revenue as a result.

Commercial and other postage rates also are declining.

The Postal Service is seeking relief from a congressional mandate to pre-fund retiree health benefits, something that neither the government nor private companies are required to do, as well as greater flexibility in setting rates.

Copyright 2016 The Associated Press.

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For the First Class parcels, the rates are staying the same FOR COMMERCIAL RATES (generate shipping label by computer at home or office):

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But the RETAIL RATES (pay at post office to clerk) have all gone down for First Class Parcel rates:

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Robert