condition mean min max ZT0-3 10.672925 8.95715 12.3887 ZT4-7 4.266534999999999 4.266534999999999 4.266534999999999 ZT8-11 1.411071 1.411071 1.411071 ZT12-15 0 0 0 ZT16-19 1.088321 1.088321 1.088321 ZT20-23 4.916215 4.916215 4.916215