condition mean min max ZT0-3 6.98983 6.98983 6.98983 ZT4-7 8.184410499999998 8.184410499999998 8.184410499999998 ZT8-11 7.746799 7.746799 7.746799 ZT12-15 7.24144 7.24144 7.24144 ZT16-19 7.6882095 7.6882095 7.6882095 ZT20-23 8.0343405 8.0343405 8.0343405