Jorge Bergoglio wasn't on many short lists to be the next pope partly because he's 76, which puts him among the 10 oldest pontiffs upon election, writes Nate Silver in the New York Times. Veering away from politics, Silver pokes around papal history and notes that the others in the top 10 served an average of five years. It's not a bad bet, then, that Pope Francis will serve somewhere around seven years, which happens to be the historical average for popes, writes Silver. That may be one reason they chose him. Another is that the average age of the voting cardinals is 72, which means many will likely get another chance to pick a pope before the cutoff age of 80.
As for the concern that picking a 76-year-old raises the risk he will serve beyond his physical and mental abilities, Benedict's stunning decision to step down probably eased those fears. "It is plausible that the resignation of Benedict XVI—which conventional wisdom held might tilt the cardinals toward electing a younger pope—in fact enabled them to choose an older one," writes Silver. Click for Silver's full column. (Read more Pope Francis stories.)