I've been holding some investment cash since as early as mid-2020 (not the lows, but just below the pre-COVID high). Have been holding steady on that and kicking myself. I'm also holding "mortgage cash," but that's different. Mortgage cash = money I would have used to pay against the mortgage but I've been earning a significantly risk-free rate on CDs and online savings accounts.

Oh well. I've reached an age and stage where it's only partly about investment returns. It also has elements of a "minimax regret" strategy. IOW, how do I minimize my chance of maximum regret? If I don't catch all of the upside, that's a bummer, but if I catch a huge downside at my age, that's even worse and would significantly impact my retirement timeline.