For example： [image] How can I generate the new list? 1.5 1.5+1.35 1.5+1.35+1.215 1.5+1.35+1.215+1.098415 , Thanks

here’s a quick DS one-liner equivalent: [image] Math.Sum(List.GetItemAtIndex(x,0…GetKeys(x) ) );

How to roll forward and sum？

Tomasz_Puchala May 17, 2017, 9:34am 2

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