You should check your investment portfolio to make certain it is properly balanced at least quarterly—if not monthly—in order to ensure that your investments are not too synchronous or correlated. Of course, this allocation depends on such factors as how much you have to invest, what your financial goals are, how much time you have before you need access to the capital (your time horizon), your tolerance to risk, and whether you are undertaking some sort of big financial challenge (losing a job, changing a job, health issues, etc.).