Each worksheet contains 6-8 tabs. The first tab has the identification of the monitoring station with its geographic coordinates. The second tab is the raw data with a count of the number of observations for each parameter monitored in the last line. In the third tab the data is filtered, the zero removed and the water quality parameters with less than 31 observations omitted. The fourth tab presents only the final numerical worksheet for statistical treatment. The fifth tab the numeric data is discretized. In this tab, the tertile, maximum, minimum and frequency of the data in each tertile per variable can be seen. In addition to the discretization equations. The sixth and seventh tabs exist only at monitoring stations that measure ammonium nitrogen. This tab presents the process of discretization of ammonium nitrogen. The last tab of all worksheets presents the discretized intervals of each water quality variable in the format required by the CBA software. The values on the last tab must be transformed into a "tra" file, the type of file required by the CBA software to generate association rules. One of the ways is to save the tab as a "txt" file and rename it as "tra" in the Windows Command Prompt.