As many others have said, it depends on what you're calculating. For my net worth, certainly.
For my savings rate, I don't count it. I don't even count my 401K contributions. For purposes of savings rate calculation, I consider my 401K contribution to be a fixed expense since under normal circumstances, I would never not contribute to it.
The purpose of understanding my savings rate for me is to know how much of my disposable income I am saving relative to my expenses. And my "adjusted income" as I like to look at it, is the sum of all money that goes in to my checking account on a monthly basis.
I subtract out my expenses, and the remainder is my savings.
What that savings number represents, to me, is an indicator of how well (or poorly) I am managing my expenses. So in one month, if my savings rate goes down, I can look at what I spent and make the proper adjustments for the next month (it's usually less entertainment, ha).