condition mean min max ZT0-3 6.733897499999999 6.48316 6.984635 ZT4-7 8.084445 8.084445 8.084445 ZT8-11 10.80445 10.80445 10.80445 ZT12-15 0 0 0 ZT16-19 9.340535 9.340535 9.340535 ZT20-23 7.594135 7.594135 7.594135