How to Invest in Momentum stocks

Holding stocks that have outperformed over a recent trailing window, usually six to twelve months, on the evidence that relative strength persists for a period before reversing. It is a rules-based approach rather than a judgement about business quality, and it requires periodic rebalancing as leadership changes.

The leading explanations are behavioural: investors underreact to news initially and then overreact as a trend becomes obvious, and institutional flows chase performance. There is no consensus on the cause, which is a reason for caution, since a pattern without a clear mechanism may not persist.

A sharp reversal where the previously winning stocks fall hardest, usually at a market inflection point when leadership rotates. These episodes are severe and fast, and they are the main reason momentum's long-run average return is achievable only by holders who do not abandon it during one.

Related but not identical. Momentum is measured by price performance over a defined window, not by attention or sentiment. In practice the two often coincide, which is why momentum portfolios frequently look like a list of whatever has been in the news, and why they concentrate quickly.

More often than most approaches, because the whole premise is holding current leaders and past leaders stop leading. Most systematic implementations reconstitute quarterly or semi-annually. Holding a momentum list indefinitely without updating it removes the mechanism the approach depends on.

Abrupt crashes at market turning points, severe concentration since winners cluster in whatever sector is leading, higher turnover and therefore higher trading costs and short-term tax, and the possibility that a well-documented pattern erodes as more capital pursues it. This is among the higher-volatility approaches on the site.