Getting ready to post a video on this. Much, MUCH more to come in my soon to be released book. Relax & Retire: Debunking Inflation Fears

From the BLS itself:
“Spending to purchase and improve houses and other housing units is treated as investment and not consumption in the CPI. Interest costs (such as mortgage interest), property taxes, real estate fees, most maintenance, and all improvement costs are part of the cost of the capital goods and are also not treated as consumption items. These non-consumption costs of owned housing are out of scope for the CPI under the cost-of-living framework that guides the index.” (emphasis mine)
The single, most important item of CPI is housing. Yet the single biggest expense homeowners have in their housing costs are not even considered in CPI! This is pure insanity!