condition mean min max ZT0-3 8.614625 8.614625 8.614625 ZT4-7 8.135677999999999 8.135677999999999 8.135677999999999 ZT8-11 8.015486 8.015486 8.015486 ZT12-15 8.284181 8.284181 8.284181 ZT16-19 8.091497 8.091497 8.091497 ZT20-23 7.732055 7.732055 7.732055