condition mean min max ZT0-3 16.62595 16.62595 16.62595 ZT4-7 14.7953 14.7953 14.7953 ZT8-11 14.21535 14.21535 14.21535 ZT12-15 13.7651 13.7651 13.7651 ZT16-19 17.141199999999998 17.141199999999998 17.141199999999998 ZT20-23 17.787950000000002 17.787950000000002 17.787950000000002