David Fuller's view I doubt that many of us will find the conclusions particularly surprising, although I am reassured by the data. On average, attempts to finesse the trading of shares shortly before or after their ex-dividend date does not pay, but it increases transaction costs.

Fullermoney maintains that the best time to lighten equity positions - either incrementally or via the implementation of a reasonably tight trailing stop - is when prices clearly soar above their trend mean approximated by the rising 200-day moving average. Institutional and other investors with large portfolios may prefer to grant covered call options in this situation.

Conversely, the best time to buy companies that you like on a valuation basis, is following a panicky plunge leading to a significant overextension relative to the decline 200-day MA. Thereafter, one can also top-up trending positions when support is encountered following pullbacks to the MA.