Year Miles MPG
2014 7546.8 44.4
2015 7333.6 43.9
2016 9368.8 44.8

This year our mileage was higher primarily due to taking a ~1000 mile road trip in western Nebraska and Colorado. Ingrid also started driving the Prius more and her own (now sold) car less on evenings and weekends.

Just like I wrote in 2015, I believe main thing lowering the fuel economy is short winter drives. My drive to and from work is just 2.5 miles per direction, and I often drive a similar distance to and from lunch. In winter, that's too little distance for the car to warm up to the point that it enters the fuel-saving EV mode while stopped at lights.