condition mean min max ZT0-3 12.370771666666666 10.183164999999999 14.320599999999999 ZT4-7 12.6425 12.6425 12.6425 ZT8-11 19.804850000000002 19.804850000000002 19.804850000000002 ZT12-15 6.65274 5.155894999999999 8.149585 ZT16-19 7.447255 7.447255 7.447255 ZT20-23 8.073215 8.073215 8.073215