Social expenditure on public pensions was equivalent to 7% of GDP on average in OECD countries in 2005 as it accounted for the biggest group of social transfers in Organisation for Economic Co-operation and Development (OECD) where 21% of GDP was spent on average in 2005 for all public social transfers.2 Our attention focuses on the related national public pension system reforms that have been taking place in nearly all countries of the world since the 1980’s.