condition mean min max ZT0-3 8.82709 8.82709 8.82709 ZT4-7 7.886064999999999 7.886064999999999 7.886064999999999 ZT8-11 7.44304 7.44304 7.44304 ZT12-15 6.8259 6.8259 6.8259 ZT16-19 8.748425000000001 8.748425000000001 8.748425000000001 ZT20-23 8.219845 8.219845 8.219845