condition mean min max ZT0-3 28.849415901 20.629442312000002 37.06938949 ZT4-7 5.45288516275 5.188217193 5.7175531325 ZT8-11 16.973801893250002 9.3411124315 24.606491355000003 ZT12-15 31.416927290000004 28.500936795 34.33291778500001 ZT16-19 44.8975471425 41.10802031 48.687073975000004 ZT20-23 49.30535947 47.316493460000004 51.294225479999994