condition mean min max ZT0-3 9.73131 8.45402 11.008600000000001 ZT4-7 8.87187 8.87187 8.87187 ZT8-11 21.763849999999998 21.763849999999998 21.763849999999998 ZT12-15 0 0 0 ZT16-19 35.997299999999996 35.997299999999996 35.997299999999996 ZT20-23 24.512700000000002 24.512700000000002 24.512700000000002