I guess this must be a regional thing dependent on population density. Where I live in the US, I have seen plots from my ancestors who died 150 years ago. I've

I guess this must be a regional thing dependent on population density. Where I live in the US, I have seen plots from my ancestors who died 150 years ago. I've never known of any relatives whose plots have been reused. Though the rate at which cemeteries are created/expanded is much lower than I would expect, even accounting for the fact that only ~50% of the population is buried. I've often wondered how to explain the discrepancy...