Can you please define what/who you mean by "the government"? The CPI changed in the 1990s after a Senate Finance Committee report said it was over-estimated (i.e., too high):
* https://en.wikipedia.org/wiki/Boskin_Commission
* https://en.wikipedia.org/wiki/United_States_Consumer_Price_I...
If you don't like how BLS (Executive Branch) reports the CPI, perhaps talk to the Senate (Legislative Branch)?