Dungeon Mastery: doomsday book part 1

Resources, whether food, fuel or otherwise yield rates can vary. The best medieval estates of France yielded 91%-93% of what was achievable while medieval France enjoyed an average yield of 35.5%. This led to colossal inequality and starvation. So you understand where finest estates in medieval France produced 92% of 36 bushels of wheat per acre, volcanicaly rich soil in 1950s New Zealand produced 80 bushels of wheat an acre under mechanised harvest.

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