condition mean min max ZT0-3 9.514989 9.514989 9.514989 ZT4-7 10.042825 10.042825 10.042825 ZT8-11 9.5236975 9.5236975 9.5236975 ZT12-15 9.1273965 9.1273965 9.1273965 ZT16-19 9.061645500000001 9.061645500000001 9.061645500000001 ZT20-23 9.123848500000001 9.123848500000001 9.123848500000001