condition mean min max ZT0-3 4.0860725 2.743715 5.4284300000000005 ZT4-7 4.451745 4.451745 4.451745 ZT8-11 1.627525 1.627525 1.627525 ZT12-15 0 0 0 ZT16-19 5.396145000000001 5.396145000000001 5.396145000000001 ZT20-23 2.70939 2.70939 2.70939