The earnings should not be your main concern when investing in a Swiss annuity. However, it is also an aspect to keep in mind, since a Swiss annuity is a way of not only protecting, but also investing your money.

Here are some of the aspects you should keep in mind:

The earnings are the income return on an investment. This refers to the interest or dividends received from an investment and is usually expressed annually as a percentage based on the investment's cost, its current market value or its face value.

To evaluate the real yield, you must take different variables into consideration, such as charges, taxes, currency development and inflation in your home country.

Make sure that your compared investment offers comparable safety, liquidity and flexibility. It should be geared towards the mid- to long-term. Ask about guarantees and for how long do you get them (preservation of your principal, minimum growth guarantees, etc.). 

Do not get blinded by high percentage return figures. The real yield is what is left for you after deduction of possible withholding taxes, charges, expenses, commissions and, last but not least, income and/or capital gains taxes back home.

The performance of your Swiss annuity is likely to vary according to the appreciation of the CHF (or other currency of your choice) against your home currency. Only make direct comparisons of investments in the same currency.