Performance chart of securities account vs. whole portfolio

I’m pretty new to PP, so sorry if this is noob question.

I was just messing around with the performance chart to see what it could show, and apparently there is the ability to graph the performance of just a securities account. Selecting this option shows a very different graph than selecting the whole portfolio. Mind, I only have one securities account in the portfolio. The thing is, is that I have no idea what this graph is showing. Could someone please explain the underlying difference between graphing just a securities account and graphing the entire portfolio when I only have one securities account in the portfolio?


The entire portfolio also comprises the non-securities (i.e. money) accounts. Does that explain the difference?

So essentially, because my cash has basically been earning nothing, the entire portfolio graph shows a slower but more steady return, i.e. a flatter chart? And the securities graph has steeper losses and gains because it’s not taking into account the cash that’s just sitting there?

Yes, that’s it. If there is (a substantial amount of) cash, there is “cash drag” which reduces the volatility, for better or worse.