condition mean min max ZT0-3 20.654600000000002 20.5461 20.7631 ZT4-7 15.690999999999999 15.690999999999999 15.690999999999999 ZT8-11 15.78235 15.78235 15.78235 ZT12-15 0 0 0 ZT16-19 18.23675 18.23675 18.23675 ZT20-23 18.8836 18.8836 18.8836