There are very few retirement products that help you accumulate a retirement nest egg and one such product is the National Pension Scheme (NPS). It is a market-linked, defined-contribution product that requires you to invest regularly in the fund of your choice. The returns are based on the performance of the fund of your choice. There are eight pension fund managers to choose from and one way to do that is by tracking the returns. Here is an analysis of the performance of various private sector NPS funds: Equity Funds, Government Bond Funds, Corporate Bond Funds.