Until 1986, data are based on mid-year estimates, calculated by applying exponential growth rates between two census. From 1986 to 2025 (up to 2010 in this dataset), data are based on the results of national population projections (cohort-component method) and are calculated by using the results of 2008 Address Based Population Registration System (ABPR) and the final results of 2008 Demographic and Health Survey.
As a result of analyses regarding the results of General Population Census (GPCs) and ABPRS, significant differences were identified between GPCs and ABPR with respect to age and sex structure as well as total population size. For this reason, retrospective population estimates based on ABPRS were made until 1985, the year in which similar results were obtained from both resources. Population projections by age groups are not available for the period between 1986-2007 since they are not considered to be reliable.
TurkStat  plan carrying out Population and Housing Census in 2011. According to the population census results, population projections will be revised. At the same time, population by age  groups  will be estimated  retrospectively. In the projections net migration is assumed to be zero.