condition mean min max ZT0-3 4.7470575 3.9251449999999997 5.56897 ZT4-7 4.8931450000000005 4.8931450000000005 4.8931450000000005 ZT8-11 8.258135 8.258135 8.258135 ZT12-15 0 0 0 ZT16-19 7.8564799999999995 7.8564799999999995 7.8564799999999995 ZT20-23 5.979095 5.979095 5.979095