condition mean min max ZT0-3 11.764773 11.764773 11.764773 ZT4-7 9.506862 9.506862 9.506862 ZT8-11 9.116029 9.116029 9.116029 ZT12-15 9.406676000000001 9.406676000000001 9.406676000000001 ZT16-19 9.438205 9.438205 9.438205 ZT20-23 9.777049 9.777049 9.777049