National Population Accounts: http://www.lilliput-information.com/index-population-account-corrections.pdf
In Britain, Austria and Denmark you do not depict the reality from the official based information when you make calculations/estimations involving ethnic descendants for research on diseases or other characters known to or expected to be descendence-related.
Naturalized and children of naturalized are counted as citizens of the nation they or their children immigrated to, and children of foreign citizens are in worst cases also counted as citizens of Britain, of Austria or of Denmark not as foreign citizens like their parents.
To correct this account according to the ethnic descendence we use the yearly (1 January) number of immigrants of foreign descendence, and corresponding to this number we add there to their expected number of births nation/area by nation/area of descendence and subtract the number of deaths in the country they immigrated to. And naturalized the same. The annuity-method then used in order to retro-estimate and project a more correct number of citizens with foreign descendence.
This means that the population-account is being corrected for the period 1979-2010 in a retro-estimation.
The difference in Denmark amount to 14 p.c. in 2010 totally for the 241 descendences in Denmark based on the birthsrates of descendence recommended by UN. And a even more realistick estimation result in a difference of 26 p.c. And given the official counting-categories will remained unchanged this difference will increase substantially in the years to come.
The variables in use are the official number of citizens of foreign descendence 1 January and the official number of naturalized each year. The parameters are the birth rates (in the case of 14 p.e. difference) recommended by UN and the total mortality rate in Denmark.
Our correction and the projections for the future do not yet include distribution on sex and ages till now.
J. E. Vig, M. Sc. (Economics), Denmark