condition mean min max ZT0-3 11.9348025 9.214705 14.654900000000001 ZT4-7 21.18485 21.18485 21.18485 ZT8-11 63.71655 63.71655 63.71655 ZT12-15 0 0 0 ZT16-19 31.867150000000002 31.867150000000002 31.867150000000002 ZT20-23 28.311149999999998 28.311149999999998 28.311149999999998