condition mean min max ZT0-3 526.445269 526.445269 526.445269 ZT4-7 357.70718 357.70718 357.70718 ZT8-11 399.23224400000004 399.23224400000004 399.23224400000004 ZT12-15 466.5588735 466.5588735 466.5588735 ZT16-19 562.27694 562.27694 562.27694 ZT20-23 447.808854 447.808854 447.808854