condition mean min max ZT0-3 19.918536 19.918536 19.918536 ZT4-7 25.0457125 25.0457125 25.0457125 ZT8-11 24.436933 24.436933 24.436933 ZT12-15 25.0893265 25.0893265 25.0893265 ZT16-19 17.274520000000003 17.274520000000003 17.274520000000003 ZT20-23 19.847015499999998 19.847015499999998 19.847015499999998