Some special elements require additional helper elements that are used during the calculation of the element's value. The helper elements are never displayed in the table. For example, when a mean is calculated based on the values in a numeric variable, two helper elements, SumX and SumN, are required to store the values to use in the calculation of the mean.

If you include the special element in an axis expression on the original variable, these helper elements are automatically created by the Table Object Model when you use UNICOM Intelligence Professional Tables Option or UNICOM Intelligence Reporter to create tables that use the special element. In some circumstances, however, you may prefer to add both the special elements and their helper elements to the metadata. You can do this by using a derived variable or creating a new one. This eliminates the need to use an axis expression, and can increase the speed of population of tables. If you are writing a metadata source component (MDSC) you may want to use this method to handle analysis elements from the original data source.

The Table Object Model automatically inserts helper elements for a special element only if the special element is in a variable. It does not add helper elements for special elements that are in helper variables, such as Ex variables in Quanvert. When setting up special elements using Quanvert metadata, you must set up the helper elements as well.