condition mean min max ZT0-3 13.277305 13.277305 13.277305 ZT4-7 10.4142885 10.4142885 10.4142885 ZT8-11 9.4364135 9.4364135 9.4364135 ZT12-15 9.9917365 9.9917365 9.9917365 ZT16-19 10.0714835 10.0714835 10.0714835 ZT20-23 10.534897999999998 10.534897999999998 10.534897999999998