How much of the money that you have set aside for investing for your retirement years should be invested in equities? There may not be a scientific answer to this, but most investment advisors would say it would depend on various factors, most important among them being your age and your appetite for risk.
So the older you grow the equity component should be progressively reduced in favour of safer fixed income investment to reduce volatility. Equities, as we all know, are risky investments.