The share fell: a sequence of questions instead of panic

The first instinct during a fall is to do something. It is more useful to work through a short list of questions, each of which has a checkable answer.

Did everything fall, or only this

If the index and comparable securities fell as much, something general happened — a rate change, an external shock, an outflow from the market. The cause is not in the company, and a decision about this particular security has nothing to do with it.

Was there news about the issuer

Check the disclosure rather than other people's commentary. A material event is one that changes future cash flows: Company news: what actually changes a valuation.

Has the reason for buying changed

If the security was bought for its dividend policy and the policy was revised, the basis is gone. If it was bought for profit growth and profit is still growing, a falling price is not an event for your hypothesis.

Has the position become too large in risk terms

A security that has fallen occupies a smaller share of the portfolio by value and often a larger one by risk, if the fall reflects deterioration. Revisiting the position size is a normal action: How to assess the risk of a position, step by step.

What not to do

Averaging down automatically "to bring the average price down". That increases the stake on a hypothesis that is not being confirmed: Eight mistakes of the first year.

And deciding on the day of a large move. A decision postponed by a day is almost always better than an immediate one.