condition mean min max ZT0-3 1.2026218333333334 0.6733055 1.63314 ZT4-7 0.310661 0.310661 0.310661 ZT8-11 1.631536 1.631536 1.631536 ZT12-15 0.18088375 0.0 0.3617675 ZT16-19 1.5691225 1.5691225 1.5691225 ZT20-23 1.0439995 1.0439995 1.0439995