Same here. Before I made my coroplast velomobile, my moving average to school @ 19.7 miles (+585 / -1039 ft) was usually around 15 - 15.5mph on a good day. If I had a headwind, I'd be closer to 14.5mph. Once in a great while I could hit 16, but that was usually with a tailwind helping me out. For the ride home using the shorter route @ 19.8 miles (+1046 / -588 ft) I'd usually be at 12.5 - 13mph moving average.

After making my velo a little over 2 weeks ago, my slowest moving average speed to school has been 16.0mph. My slowest moving average home taking the shorter route is currently 13.3mph. Middle of last week I started taking the longer route home, which bypasses the steeper hill to my house @ 22.2 miles (+1096 / -639 ft). My moving average taking that way has been 13.7 - 14.2mph.

My fastest commute to school ever was last Monday at 17.5mph moving average (15.8mph average including stops) and 39.2mph max: http://ridewithgps.com/trips/456393.