Finally got enough data points to post my chart.
My car is a 2007 Nissan Versa with the 6 speed manual transmission.
Data collect over two trips south and back. I was surprised to find that the time spent with the AC on was really no different than with the AC of as far as fuel economy is concerned. I am not going to bother differentiating next time I do a set of runs.
The size represents the distance traveled. Most are around 15km. All data points are recorded with cruise control on, engine warmed up, and no traffic on the road. There are 85 data points representing 1301 km traveled.
You can basically ignore the yellow points. They have extra variables like running in a different gear, following a truck, and driving on gravel roads.