-20 to 40C isn't as nice as 0-100, but it's not terrible. AFAIR 0-100 wasn't the goal anyway. 0F was just the lowest they could reach in a lab setting at the t

-20 to 40C isn't as nice as 0-100, but it's not terrible. AFAIR 0-100 wasn't the goal anyway. 0F was just the lowest they could reach in a lab setting at the time. Then they chose to have 180 degrees between water freezing and boiling.