After about 5 years of wild swings it has been stable for the past 11 years. Now compare that to what happened to various other currencies that were not linked to anything. During the last weeks, commodity prices on the mercantile exchange tumbled, as you will see if you check the financial papers. I have no idea. The reason is the CPI is an arbitrary measure, and many quantities may be adjusted before you will see adjustments in prices.
Governments have less tax revenues.
They cut spending on schools, medicare, bridges, highways etc. The government will diminish the quantity of quality services. But nothing will show up in the price index. Remember that the whole idea of changes in price indices reflecting anything of interest is based on the view that most goods and services are priced through trial and error by suppliers. It is not clear what changes in CPI or other price indices reflect when governments do the pricing.