In the movie Back to the Future II, Biff travelled back in time to give himself a copy of a sports book which listed the results of every major sporting event for 50 years. How often have we wished we had something similar for investing — would having such an object enable you to invest better though?

You’ve done everything right: You’ve set a long investment horizon to ensure positive returns, and reduced your equity allocation to make room for bonds to absorb shocks in the market. So what should one do when the invested assets suddenly don’t seem to behave anymore?