condition mean min max ZT0-3 22.9359388025 19.807156335000002 26.06472127 ZT4-7 6.90072953075 6.005630652999999 7.7958284085 ZT8-11 7.007877015749999 5.6882510175 8.327503014 ZT12-15 8.18541869125 8.1205488835 8.250288499 ZT16-19 9.99183679225 9.027197624 10.9564759605 ZT20-23 12.6050177575 11.90379579 13.306239725000001