condition mean min max ZT0-3 8.17012 8.17012 8.17012 ZT4-7 7.04179 7.04179 7.04179 ZT8-11 7.9230149999999995 7.9230149999999995 7.9230149999999995 ZT12-15 11.6849 11.6849 11.6849 ZT16-19 13.14655 13.14655 13.14655 ZT20-23 12.12895 12.12895 12.12895