I can’t swear to it but think our home was valued at the purchase price in 1999 in PA.
This is an area where the counties have authority, so it maybe that where you lived they did assess when a purchase was made. That doesn’t seem fair though if the neighbors’ values are decades old.
We had an assessment problem. We put in an above ground pool and our assessment went up. We tried to get it lowered, as it was not legal. We failed. A new asscessor took over and upped everyone’s assessments. We placed another grievance pointing out what had happened to us. We were the only ones to get lowered. They said we had been unfairly treated and they wanted to make it up to us.