condition mean min max ZT0-3 4.799505 4.781885 4.817125000000001 ZT4-7 3.5182149999999996 3.5182149999999996 3.5182149999999996 ZT8-11 3.28153 3.28153 3.28153 ZT12-15 0 0 0 ZT16-19 5.123885 5.123885 5.123885 ZT20-23 5.266265 5.266265 5.266265