Which formula is used to count unique values in a data range?

Using the COUNTIF function with unique criteria is effective for counting unique values within a specific range of data. The COUNTIF function allows the user to specify a condition, and it counts the number of times this condition is met. By applying unique criteria, such as using a function to filter distinct values prior to counting, the user can accurately determine how many different entries exist in the specified range.

For instance, if the user has a list of items that may have duplicates, employing COUNTIF with a set of criteria designed to identify the distinct entries enables the calculation of unique values. This approach is essential when needing to analyze datasets to understand diversity in entries, such as customer names, product identifiers, or any other relevant information that does not need to be counted multiple times for duplicates.

This method surpasses other functions, as they either focus on different types of computational outputs or may not be tailored specifically to counting conditions, as seen with the other options. Therefore, leveraging COUNTIF alongside a unique criterion directly addresses the requirement of counting distinct values in a dataset effectively.