But not likely. As this FiveThirtyEight piece explains, steroids are not likely the cause of the increased power exhibited this year by Major League Baseball. The article goes into a bit of detail, but this set of small multiples does a nice job comparing several other factors that could be at play.

What I like about the piece is how each line chart is centred on the year where the factor came into play. And then to the right and left are ten years before and after. Maybe a little bit more could have been done to highlight the differing years—I admit that I missed that at first—but the concept itself is solid.
Credit for the piece goes to the FiveThirtyEight graphics department.