Why on earth would kg/person not be a valid unit of measurement simply because the individuals in question are dead? Eurostat, to take just one example, uses it
. In general, per capita measures are commonly used in a large number of social science disciplines.
Also, SnakeTongue: A week or so ago, you said Roberto's calculation resulted in inverse length. Please lead us through you got that result if kg/kg doesn't equal 1.