Ken French’s recently updated global factor data shows the global size and value premiums were basically flat for the past 10 years (the value premium was actually about –1 percent per year over this span). This long-term historical result has surprised many people and naturally led some to ask whether these premiums can be expected in the future. Figure 1 graphs the one-, three-, five-, 10-, 15- and 20-year average size and value premiums using the global data set.