condition mean min max ZT0-3 9.4294275 8.678395 10.18046 ZT4-7 9.537345 9.537345 9.537345 ZT8-11 24.02935 24.02935 24.02935 ZT12-15 0 0 0 ZT16-19 24.004649999999998 24.004649999999998 24.004649999999998 ZT20-23 14.897 14.897 14.897