condition mean min max ZT0-3 16.143553 16.143553 16.143553 ZT4-7 33.581391499999995 33.581391499999995 33.581391499999995 ZT8-11 42.2942195 42.2942195 42.2942195 ZT12-15 24.5647995 24.5647995 24.5647995 ZT16-19 16.6611515 16.6611515 16.6611515 ZT20-23 15.6721495 15.6721495 15.6721495