The Postal Regulatory Commission approved a one-cent increase last month to keep pace with inflation, but said it tacked on an additional two cents -- bringing the total to $0.49 -- to help make up for losses during the recession.
The Postal Service was ordered "develop a plan to phase out the rates once they have produced the revenue justified by their request," the PRC said.
The agency reported $5 billion in losses in the 2013 fiscal year, after losing $16 billion in 2012.
It is also considering reducing mail delivery and increasing package delivery, which brings in more revenue.
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