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The Row Number is an element that lists the respective row numbers in a List incrementally.

Where to Find

Figure 1: Row Number element listed under Display Column section.

It can be found under the Display Column section in the List Builder. You may also find it using the Search Palette by keying in "Row Number".

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Simply drag and drop the element into the List. Remember to Save your work by clicking on the blue glowing "Save" button on the upper right corner.

Figure 2: Adding Row Number column to a List.

Result