I have a route that is @25 miles with a couple of steep climbs nearing 13% for about 5 of those miles. I use a GPS Garmin to track my mileage and speed and have a personal average speed record for that route that I constantly try to improve on. But my average is only important to me when I finish that route. At 73 I'm still competing with myself and getting excited when I break my record, but only on that route. Otherwise, when I go for a ride I just push myself for the exercise aspect, even when just riding to the store. You done good increasing your average by that much for such a long ride. Pat yourself on the back and see if you can beat it in the future. It's a goal worth striving for. Good luck, Smokey