Size premium data is generally available from two sources: Morningstar's (formerly Ibbotson & Associates') Stocks, Bonds, Bills & Inflation and Duff & Phelps' Risk Premium Report.
Rex A. Sinquefeld and Roger G. Ibbotson, Annual Yearbooks dealing with Stocks, Bonds, Bills and Inflation (relevant to long term returns to US financial assets).
Roger Moore | Roger Corman | Roger Federer | Roger Daltrey | Who Framed Roger Rabbit | Roger Waters | Roger Maris | Roger McGuinn | Beaumont-le-Roger | Roger Zelazny | Roger Ebert | Roger Clemens | Roger Smith | Roger Miller | Roger Tory Peterson | Roger Vadim | Roger Sanchez | Roger Blench | Roger Williams | Roger & Me | Roger Taylor | Roger Staubach | Roger Heim | Roger Goodell | Roger Douglas | Roger Williams (theologian) | Roger Sherman | Roger Mayweather | Roger Lancelyn Green | Roger B. Taney |