Democrats experience neither highs nor lows. What's it like? Eh.

I missed Mike Sances' post about the "partisan trust gap" at the Monkey Cage when it first came out, but it's really quite interesting. Sances notes that Republicans tend to have much more trust in government during Republican presidential administrations, and Democrats do the same when their party controls the White House. One thing that is not really discussed in the post, though, is the asymmetrical responses by the parties. Note Sances' graph:

It looks like there's a lot more variance in Republicans' feelings toward government than in Democrats' feelings toward government. What's up with that?