condition mean min max ZT0-3 1.9114590532500002 0.42259419200000004 3.4003239145000004 ZT4-7 12.73034260375 11.0904297675 14.370255440000001 ZT8-11 19.9094889525 17.6367273 22.182250605 ZT12-15 41.7455908 36.199263285 47.291918315000004 ZT16-19 34.87121103 33.04959834 36.69282372 ZT20-23 23.61854362 22.27998719 24.95710005