condition mean min max ZT0-3 5.76843638425 0.765130483 10.7717422855 ZT4-7 62.432318445 45.310108575 79.554528315 ZT8-11 82.843125725 75.78605034 89.90020111 ZT12-15 46.75919016500001 32.580681555000005 60.937698775 ZT16-19 15.9854678525 15.503987355 16.46694835 ZT20-23 19.616756005 18.006730304999998 21.226781705