Yellow book fever

Today, I realized that all of my recent reads have had yellow covers. Does this mean something? Am I attracted to yellow book covers? I suppose if this was true I'd be spending a lot of time reading the phone book. Or, is there just some new tendency to use yellow in book covers? Has there been scientific research on this?

Here's my list:

Tree of Smoke - predominately yellow cover

The Best American Short Stories 2005 - entirely yellow cover

No one belongs here more than you - entirely yellow

The Subject Steve - orangy-yellow cover

Strange . . . And look at how similar the layout and font is in both No one and Steve.

That's all. Nothing else.