condition mean min max ZT0-3 21.4461 21.4461 21.4461 ZT4-7 19.490949999999998 19.490949999999998 19.490949999999998 ZT8-11 17.65955 17.65955 17.65955 ZT12-15 17.6784 17.6784 17.6784 ZT16-19 19.208550000000002 19.208550000000002 19.208550000000002 ZT20-23 20.592 20.592 20.592