I’ve owned 5 personal properties during the charted timeframe and Zillow and the like constantly has a 10-20% error rate between their valuation calculation and what the market value actually is. It has been under/over but rarely correct. I very recently sold a rental home for $100K less than Zillow, Redfin, and Realtor.com think I should have ($500k vs $600k, where $500k is actually near all time record high within 1 square mile of its metro area). Anyways, it’s hard for me to trust this enough to make any conclusions given what I’ve seen from their data.