Answer:
the expected rate of return of an investment is calculated using the following formula:
Re = risk free + beta x (market risk - risk free)
market risk - risk free = risk premium
another way of calling market risk is systematic risk
the beta for the whole market is 1, so we can simplify the equation:
market Re = risk free + risk premium
If the expected rate of return is barely above the risk free rate, that means that the market risk (or systematic risk) is not very high, therefore, resulting in a low risk premium. I.e. market risk is very low, probably because the economy is doing very well in general terms and the inflation rate is probably also very low.