condition mean min max ZT0-3 0.56956841225 0.35035321799999997 0.7887836065 ZT4-7 2.9345016945 1.5055883085000001 4.3634150805 ZT8-11 9.59955247225 7.279318174499999 11.91978677 ZT12-15 7.456688731 5.3282400359999995 9.585137426 ZT16-19 4.961341628 4.736684979 5.1859982769999995 ZT20-23 10.266258339250001 8.3051060985 12.22741058