condition mean min max ZT0-3 6.32234 5.786614999999999 6.858065 ZT4-7 6.701594999999999 6.701594999999999 6.701594999999999 ZT8-11 6.051635 6.051635 6.051635 ZT12-15 0 0 0 ZT16-19 6.68281 6.68281 6.68281 ZT20-23 6.425305 6.425305 6.425305