Shadow stats is a crank blog with absolutely no validity. Choose your debunking source, but the owner of the blog literally just adds an amount to the official rate that he thinks represents the government error. There’s no calculation, there’s no “pre-1980 methodology”, just one dude’s vibes. If the rate has averaged 9% over the past 25 years, you’d be talking about over 750% inflation since 2000. You can buy any manner of new car today for $35k - could you buy a new car for $5k in 2000? Did a gallon of gas cost $0.40/gallon? Could you rent a modern $1,500 apartment for $200/month?

https://www.fullstackeconomics.com/p/no-the-real-inflation-r...

If he actually did the work of calculating using the earlier methodology, it could actually be interesting, but it probably wouldn't say what he thinks. But yeah, that site is BS.