The monthly market watcher is more attentive than the long-term, buy-and-hold investor.  Monthly market followers may evaluate their investments and/or reallocate several times a year, often doing reseach, evaluating, and making decisions on the basis of their quarterly or monthly statements.   They have more of a "show-me" attitude toward their investments, but require a substantial period for proof of high or low performance before passing judgment on either the success or the failure of an investment strategy.  This type of market watcher pays attention to the medium-term momentum in markets as related to the fundamentals of business, finance, and the national and global economies.  Rather than depending upon the long-run, the monthly investor is mindful of the need for periodic interaction with the market, as implied in the admonition of a famous economist that, "in the long run, we are all dead."  In order to stay ahead of the market, the monthly market watcher needs to visualize current market trends averaged on a monthly (20-day, meaning 20-trading-session) time scale.   Chart products for the monthly investor are collections of 20-day-average charts, updated weekly.  They are identified by a prefix consisting of  "M" and a second character that indicates the type of averaging, e.g., "D" indicates daily updating while "W" designates weekly updating, and "M" denotes monthly updating.