condition mean min max ZT0-3 5.612432500000001 4.92724 6.297625 ZT4-7 5.2237849999999995 5.2237849999999995 5.2237849999999995 ZT8-11 7.9028 7.9028 7.9028 ZT12-15 0 0 0 ZT16-19 7.973879999999999 7.973879999999999 7.973879999999999 ZT20-23 6.445805 6.445805 6.445805