condition mean min max ZT0-3 16.148753 16.148753 16.148753 ZT4-7 11.942636499999999 11.942636499999999 11.942636499999999 ZT8-11 12.193660000000001 12.193660000000001 12.193660000000001 ZT12-15 11.4081235 11.4081235 11.4081235 ZT16-19 11.945867499999999 11.945867499999999 11.945867499999999 ZT20-23 13.5703595 13.5703595 13.5703595