condition mean min max ZT0-3 11.864775 11.590399999999999 12.13915 ZT4-7 12.7168 12.7168 12.7168 ZT8-11 8.27991 8.27991 8.27991 ZT12-15 0 0 0 ZT16-19 9.28951 9.28951 9.28951 ZT20-23 11.988299999999999 11.988299999999999 11.988299999999999