The data below the graph seems to update, but sometimes it seems not to - for example, the avg for 2014 is 24.9mpg when unfiltered, or when filtered this way. Not impossible, but seems unlikely. I'm guessing that this was just a coincidence, and that the data below the graph is Ok. But you might want to double-check it after looking at the graph.
But the kicker is, the graph itself never changes. Perhaps it's not meant to, but I expected it do, and it didn't.
Screenshots attached, but this links are probably easier to use.