flds = ("VALUE", "COUNT")

dct = {row[0]:row[1] for row in arcpy.da.SearchCursor(i, flds)}

sumcnt = sum(dct.values())

newraster = ExtractByAttributes(str(i), "VALUE>=14")

for j in newraster:

    flds1 = ("VALUE", "COUNT")

    dct1 = {row[0]:row[1] for row in arcpy.da.SearchCursor(j, flds)}

    sumcnt1 = sum(dct1.values())

    percentage=(sumcnt/sumcnt1)

    print percentage