defined contribution pension types and reducing future payment amounts (by, for example, adjusting the formula that determines the level of benefits) Increasing resources to fund pensions by increasing contribution rates and raising taxes Background The ratio of workers to pensioners (the "support ratio") is declining in much of the developed world. This is due to two demographic factors: increased life expectancy coupled with a fixed retirement age, and a decrease in the fertility rate. Increased life expectancy (with fixed retirement age) increases the number of retirees at any time, since individuals are retired for a longer fraction of their lives, while decreases in the fertility rate decrease the number of workers. In 1950 there were 7.2 people aged 20–64 for every person of 65 or over in the OECD countries. By 1980, the support ratio dropped to 5.1 and by 2010 it was 4.1. It is projected to reach just 2.1 by 2050. The average ratio for the EU was 3.5 in 2010 and is projected to reach 1.8 by 2050. Examples of support ratios for selected countries and regions in 1970, 2010, and projected for 2050 using the medium variant: Pension computations Pension computations are often performed by actuaries using assumptions regarding current and future demographics, life expectancy, investment returns, levels of contributions or taxation, and payouts to beneficiaries, among other variables. One area of contention relates to the assumed annual rate of investment return. If a higher investment return is assumed, relatively lower contributions are demanded of those paying into the system. Critics have argued that investment return assumptions are artificially inflated, to reduce the required contribution amounts by individuals and governments paying into the pension system. For example, bond yields (the return on guaranteed investments) in the US and elsewhere are low (and the U.S.and other stock markets did not consistently beat inflation between 2000 and 2010). But many pensions have annual investment return assumptions in the 7–8% p.a. range, which are closer to the pre-2000 average return. If these rates were lowered by 1–2 percentage points, the required pension contributions taken from salaries or via taxation would increase dramatically. By one estimate, each 1% reduction means 10% more in contributions. For example, if a pension program reduced its investment return rate assumption from 8% pa to 7% pa, a person contributing $100 per month to their pension would be required to contribute $110. Attempting to sustain