condition mean min max ZT0-3 6.519155 6.519155 6.519155 ZT4-7 5.46678 5.46678 5.46678 ZT8-11 5.387485 5.387485 5.387485 ZT12-15 5.160495 5.160495 5.160495 ZT16-19 6.3971 6.3971 6.3971 ZT20-23 5.458024999999999 5.458024999999999 5.458024999999999