condition mean min max ZT0-3 18.63035 17.3889 19.8718 ZT4-7 13.40995 13.40995 13.40995 ZT8-11 11.87745 11.87745 11.87745 ZT12-15 0 0 0 ZT16-19 16.9866 16.9866 16.9866 ZT20-23 17.234949999999998 17.234949999999998 17.234949999999998