condition mean min max ZT0-3 9.538025 9.538025 9.538025 ZT4-7 9.107021 9.107021 9.107021 ZT8-11 9.3977695 9.3977695 9.3977695 ZT12-15 10.6145505 10.6145505 10.6145505 ZT16-19 9.473736500000001 9.473736500000001 9.473736500000001 ZT20-23 10.3773145 10.3773145 10.3773145