First,
the historical equity risk premium was high and decades could pass before a big - enough crash, making it very costly to sit in cash.
Not exact matches
Estimates of the future
equity risk premium should start with
historical results and then adjust for expected shifts in stock market variability and non-repeatability of unusual past cash flows.
... formal asset valuation models (extrapolations of
historical return data) provide the most (least) predictive estimates of the future
equity risk premium.
Below is a chart of the
historical S&P GSCI Energy TR index levels versus the
equity risk premium as measured by the S&P 500 Energy Total Return monthly minus the S&P 500 Energy Corporate Bond Index Total Return monthly.
In
historical oil bottoms, the energy
equity risk premium, that measures the difference between the S&P 500 Energy Sector and the S&P 500 Energy Corporate Bond Index, has switched from a discount to a
premium.