condition mean min max ZT0-3 28.315914 28.315914 28.315914 ZT4-7 35.224378 35.224378 35.224378 ZT8-11 38.724377000000004 38.724377000000004 38.724377000000004 ZT12-15 38.690183000000005 38.690183000000005 38.690183000000005 ZT16-19 41.7013905 41.7013905 41.7013905 ZT20-23 43.957016499999995 43.957016499999995 43.957016499999995