condition mean min max ZT0-3 1.1476143333333333 0.895189 1.552335 ZT4-7 0.7972565 0.7972565 0.7972565 ZT8-11 0.6537665 0.6537665 0.6537665 ZT12-15 1.6003349999999998 1.485105 1.715565 ZT16-19 0.9856635 0.9856635 0.9856635 ZT20-23 1.96953 1.96953 1.96953