Measuring dependency ratios using National Transfer Accounts

It is now widely recognised that the socio-economic changes that ageing societies will bring about are poorly captured by the traditional demographic dependency ratios (DDRs), such as the old-age dependency ratio that relates the number of people aged 65+ to the working-age population. Compared to the older people of today, future older generations will be in better health, and will likely work longer. However, strictly from a public finance perspective, the extent to which the DDRs capture the challenges that stem from ageing depends on future changes in the age structure of the population, in behavioural patterns, and in age-related public transfers. Combining population projections and National Transfer Accounts (NTA) data (i.e., data on age-specific public transfers), we construct a ‘transferbased’ demographic dependency ratio for seven European countries up to 2050. We then compare the quantitative impact of the transfer-based DDR with that of the traditional DDR for three different policy responses to population ageing: net immigration, healthy ageing, and longer working lives. This is done by linking agespecific public health transfers and labour market participation rates to changes in mortality. Four main findings emerge. First, the simple old-age dependency ratio overestimates the future public finance challenges faced by the countries studied, and substantially so for some countries, such as Austria, Finland, and Hungary. Second, healthy ageing (i.e., keeping health transfers constant for a given mortality rate) has a modest effect on public finances, except in the case of Sweden, where it plays an important role. Third, the long-run effect of immigration is captured well by the traditional DDR measure if the common assumption that immigrants are similar to natives is maintained. The immediate to short-term impact of immigration tends to be overstated by the traditional DDR measure. Finally, increasing the average length of working life is central to addressing the public finance challenge of ageing. We estimate that extending the average length of working life by three to five years over the next 25 years – roughly in line with the gain in life expectancy – will substantially reduce the impact of ageing on public transfers.