condition mean min max ZT0-3 8.69724 8.380295 9.014185000000001 ZT4-7 6.58106 6.58106 6.58106 ZT8-11 7.0305800000000005 7.0305800000000005 7.0305800000000005 ZT12-15 0 0 0 ZT16-19 7.07194 7.07194 7.07194 ZT20-23 8.34121 8.34121 8.34121