they are restricted from lowing their rates per the same 2006 bill cited above. in addition, they have to pre-fund their pension benefits well into the future in ways that other privatized companies would never do. the obligation is overwhelmingly crippling. i don't remember the exact figures, but in 2006 USPS profited somewhere around ~$10M, and in 2009—three years after the law was enacted—they lost close to ~4B. i believe it was estimated that ~3/4 of those losses were directly associated with that law.