condition mean min max ZT0-3 8.77586 8.77586 8.77586 ZT4-7 5.51623 5.51623 5.51623 ZT8-11 7.27747 7.27747 7.27747 ZT12-15 8.934180000000001 8.934180000000001 8.934180000000001 ZT16-19 13.34975 13.34975 13.34975 ZT20-23 8.134165 8.134165 8.134165