condition mean min max ZT0-3 193.381782 193.381782 193.381782 ZT4-7 175.07304699999997 175.07304699999997 175.07304699999997 ZT8-11 190.065851 190.065851 190.065851 ZT12-15 198.7460275 198.7460275 198.7460275 ZT16-19 212.39944 212.39944 212.39944 ZT20-23 196.74339550000002 196.74339550000002 196.74339550000002