condition mean min max ZT0-3 8.479381666666667 7.86232 9.023399999999999 ZT4-7 8.96604 8.96604 8.96604 ZT8-11 11.51555 11.51555 11.51555 ZT12-15 12.794025 12.75695 12.8311 ZT16-19 12.956949999999999 12.956949999999999 12.956949999999999 ZT20-23 8.713104999999999 8.713104999999999 8.713104999999999