condition mean min max ZT0-3 5.393805 4.94431 5.8433 ZT4-7 3.79231 3.79231 3.79231 ZT8-11 4.279615 4.279615 4.279615 ZT12-15 0 0 0 ZT16-19 7.349595 7.349595 7.349595 ZT20-23 7.04912 7.04912 7.04912