condition mean min max ZT0-3 9.13716 9.13716 9.13716 ZT4-7 8.884025999999999 8.884025999999999 8.884025999999999 ZT8-11 9.2829825 9.2829825 9.2829825 ZT12-15 9.08512 9.08512 9.08512 ZT16-19 10.6462985 10.6462985 10.6462985 ZT20-23 8.9756185 8.9756185 8.9756185