In 2015, the average points differential was just 11.06 points per game. That may not mean much in the abstract, but it’s the lowest in 20 years. Take a look:

What was driving the close games this year? It’s mostly because the “losing teams” wound up scoring more points, but the average points scored by the winning team did dip slightly in 2015, too:

With the losing teams scoring more points and games getting closer, I wondered if underdogs had a better record this year. As it turns out, that wasn’t the case. Underdogs were slightly better than 50/50 this year against the spread, but nothing out of the ordinary: