What have average investment asset class risk premiums been over long periods? - Personal Investment Management > Investment... What have average investment asset class risk premiums been over long periods? - Personal Investment Management > Investment Returns and Securities Market Risk Premiums Articles - Financial Articles, Over the past two hundred years, real or non inflationary equity market returns have averaged just under 7%. During the 19th century, cash and bond returns “were king” and additional equity risk returns were relatively small. In the 20th century and particularly during the second half of that century, investors were much more richly rewarded for carrying the risks associated with equity investments. in Public bookmarkswith assetaverageclassinvestmentperiodspersonalpremiumsrisk