Trend analysis is the widespread practice of collecting information and attempting to spot a pattern.
In some fields of study, the term has more formally defined meanings.
[1][2][3] Although trend analysis is often used to predict future events, it could be used to estimate uncertain events in the past, such as how many ancient kings probably ruled between two dates, based on data such as the average years which other known kings reigned.
In project management, trend analysis is a mathematical technique that uses historical results to predict future outcome.
[4][5] In statistics, trend analysis often refers to techniques for extracting an underlying pattern of behavior in a time series which would otherwise be partly or nearly completely hidden by noise.