condition mean min max ZT0-3 3.0215025 2.98297 3.060035 ZT4-7 6.31365 6.31365 6.31365 ZT8-11 9.839855 9.839855 9.839855 ZT12-15 0 0 0 ZT16-19 7.793374999999999 7.793374999999999 7.793374999999999 ZT20-23 4.67024 4.67024 4.67024