condition mean min max ZT0-3 6.56111 6.56111 6.56111 ZT4-7 1.8553700000000002 1.8553700000000002 1.8553700000000002 ZT8-11 2.93797 2.93797 2.93797 ZT12-15 71.05555 71.05555 71.05555 ZT16-19 64.43165 64.43165 64.43165 ZT20-23 25.171149999999997 25.171149999999997 25.171149999999997