condition mean min max ZT0-3 10.652222221 10.652222221 10.652222221 ZT4-7 14.07888889 14.07888889 14.07888889 ZT8-11 15.215 15.215 15.215 ZT12-15 18.009999999999998 18.009999999999998 18.009999999999998 ZT16-19 15.868888887666667 15.868888887666667 15.868888887666667 ZT20-23 18.249999999 18.249999999 18.249999999