condition mean min max ZT0-3 17.39215 17.39215 17.39215 ZT4-7 6.82207 6.82207 6.82207 ZT8-11 11.04875 11.04875 11.04875 ZT12-15 13.31235 13.31235 13.31235 ZT16-19 28.9776 28.9776 28.9776 ZT20-23 29.5529 29.5529 29.5529