condition mean min max ZT0-3 8.565750000000001 8.565750000000001 8.565750000000001 ZT4-7 7.030555 7.030555 7.030555 ZT8-11 6.577735 6.577735 6.577735 ZT12-15 8.088015 8.088015 8.088015 ZT16-19 9.8281 9.8281 9.8281 ZT20-23 8.848424999999999 8.848424999999999 8.848424999999999