condition mean min max ZT0-3 4.1171925 4.09601 4.138375 ZT4-7 3.0703300000000002 3.0703300000000002 3.0703300000000002 ZT8-11 3.112215 3.112215 3.112215 ZT12-15 0 0 0 ZT16-19 4.099975 4.099975 4.099975 ZT20-23 2.4533199999999997 2.4533199999999997 2.4533199999999997