condition mean min max ZT0-3 5.092090000000001 4.743125 5.441055 ZT4-7 5.56597 5.56597 5.56597 ZT8-11 3.19602 3.19602 3.19602 ZT12-15 0 0 0 ZT16-19 7.6155 7.6155 7.6155 ZT20-23 8.91839 8.91839 8.91839