This is why national per capita consumption is the best (the most exhaustive) way to assess water footprints: it adds green, blue, and grey water components as well as all virtual water (water that was required for the growth or production of imported food and manufactured goods).[18] Domestic blue water use (all values are in cubic meters per year per capita) ranges from just over 29 in Canada and 23 in the USA to about 11 in France, 7 in Germany, and about 5 in China and India, and to less than 1 in many African countries.[19]
