Markets fall. They have fallen in roughly one out of every three years on record, and they will fall again. The single most important thing we do for our clients is to make those falls — which are inevitable — into a non-event for the plan.
Three rules
First: do nothing for forty-eight hours. Almost every regrettable financial decision in our careers was made in the first forty-eight hours of a market drop.
Second: look at the plan, not the portfolio. The plan was built knowing this would happen. The portfolio is just today's score.
Third: rebalance, do not flee. If equities have fallen and bonds have held, you now own less of the cheap thing and more of the expensive thing. That is a buying opportunity, not a selling one.