condition mean min max ZT0-3 6.9659175 5.92471 8.007125 ZT4-7 9.31389 9.31389 9.31389 ZT8-11 2.89594 2.89594 2.89594 ZT12-15 0 0 0 ZT16-19 6.363905 6.363905 6.363905 ZT20-23 7.39452 7.39452 7.39452