An alternative approach uses a component that I called the Cumulative Framework, but you don’t actually use it quite like a regular component, as you unlink (disconnect) it and then modify a Rule Engine and Math Formula contained inside it. It is built using 3 other components that work with a recursive loop. Those workings are not something you need to know about though.
This workflow contains a demo of the cumulative framework providing the same solution as the Column Expressions example.
Conditional Cumulative Demo with Cumulative Framework.knwf (134.9 KB)
The method for using the Cumulative Framework component is best demonstrated with a demo video (it contains no audio). Apologies that the video quality is not great because it had to stay under the forum’s 4MB limit.
If you are interested, the “cumulative framework” is described further in my forum post from December 2023…