condition mean min max ZT0-3 9.653294 9.653294 9.653294 ZT4-7 10.829067 10.829067 10.829067 ZT8-11 11.42099 11.42099 11.42099 ZT12-15 10.1781325 10.1781325 10.1781325 ZT16-19 10.465867 10.465867 10.465867 ZT20-23 10.743324999999999 10.743324999999999 10.743324999999999