“…For each justice, the Compendium gives lifetime percentages of voting liberal in each category; it also gives yearly percentages for four of the most common categories: criminal procedure, civil rights, first amendment, and economics. There is change in justices' voting propensities over time (Segal, Timpone, & Howard, 2000), sometimes quite pronounced, and sometimes quite sudden. Consequently, in determining justices' voting propensities I typically used the mean over three years or the duration of the natural court, whichever was longer.…”