condition mean min max ZT0-3 22.937777779999998 22.937777779999998 22.937777779999998 ZT4-7 79.21222222333333 79.21222222333333 79.21222222333333 ZT8-11 57.63611111 57.63611111 57.63611111 ZT12-15 21.49777778 21.49777778 21.49777778 ZT16-19 11.277777779 11.277777779 11.277777779 ZT20-23 7.608888889 7.608888889 7.608888889