To analyze the average revenue per product in different regions over time, you need to use two fields that contain numeric, quantitative values that you can measure and aggregate. Quantity and Revenue are both measures that fit this criterion. You can multiply Quantity and Revenue to get the total sales for each product, and then divide by the number of products to get the average revenue. You can also use these measures to create charts and tables that show the trends and comparisons over time and across regions. References:
* Dimensions and Measures, Blue and Green - Tableau
* Tableau Certified Data Analyst Study Guide

To connect to a tab-delimited data file named sales.tsv, you should select the option To a File > Text file in Tableau Desktop. This option will allow you to browse and select the file from your local or network drive and connect to it as a data source. You can then specify the text file properties, such as the delimiter, the text qualifier, and whether the first row contains column names. You can also join, union, or blend the data with other data sources if needed. References:
* Text File - Tableau
* Tableau Certified Data Analyst Study Guide

https://kb.tableau.com/articles/howto/filtering-data-with-a-parameter?lang=fr-fr After creating a parameter named Choose Region, you want to use it to filter the chart based on the user's selection. To do this, you would create a calculated field with the formula [Region] = [Choose Region] and add this calculated field to the Filters card. This will dynamically filter the chart to display data only for the region that matches the user's selection in the Choose Region parameter.