condition mean min max ZT0-3 2.1723274999999997 1.8763999999999998 2.468255 ZT4-7 2.11654 2.11654 2.11654 ZT8-11 1.90889 1.90889 1.90889 ZT12-15 0 0 0 ZT16-19 2.800955 2.800955 2.800955 ZT20-23 2.266115 2.266115 2.266115