condition mean min max ZT0-3 11.360096 11.360096 11.360096 ZT4-7 11.831949999999999 11.831949999999999 11.831949999999999 ZT8-11 11.917326 11.917326 11.917326 ZT12-15 11.6181695 11.6181695 11.6181695 ZT16-19 10.095450499999998 10.095450499999998 10.095450499999998 ZT20-23 11.82587 11.82587 11.82587