The Mann-Kendall test is a method of identifying whether or not there is a trend in a set of data points. The nice thing about the Mann-Kendall test is that the test can identify trends even if there is a seasonal component to the data (but not if the data is collected seasonally!). Also, the Mann-Kendall test is a non-parametric test. This means that the Mann-Kendall test works for data that does not fit a normal distribution (bell curve). The Mann-Kendall test is a useful computation that is perhaps most often used within the environmental, health, and social sciences but can be used in any situation where trends are important.
This recipe provides an implementation of the Mann-Kendall test in DAX.