how to update value between row iterations

[gonhaddock]

Hello @lama12345
I think this is a job for ‘Recursive Loop’ nodes set

Time Series Forecasting with differenced series

Hello, how can I get the original values back from a forecasted differenced time series? The picture below shows my original series (Original GDP), the lagged column and finally the differenced column. I used the differenced column to forecast 2001 - 2003. The results from the forecast are shown in column E. To get the original values I used the last available original value (2000Q4) plus the forecast. But afterwards I need the “Forecasted Original” previous value to calculate the next original…

unless @Daniel_Weikert hides a trick in his hat

BR