condition mean min max ZT0-3 7.786524999999999 7.786524999999999 7.786524999999999 ZT4-7 5.762745 5.762745 5.762745 ZT8-11 5.754765 5.754765 5.754765 ZT12-15 5.96054 5.96054 5.96054 ZT16-19 7.09636 7.09636 7.09636 ZT20-23 6.997195 6.997195 6.997195