Furthermore please check these posts they seems very comprehensive and detailed (more complex what you need but maybe they will give you some inspiration) I am sure you will find what you are looking for:
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…
Hello, I am working with a system of two equations where one’s input will be used as the other’s output. The first equation calculates the quantities to order for a month (n), and the second one the stock projection for the next month (n+1). This later will be injected as an input to calculate the ordering quantities for the month n+1 which in turn will be injected into the second equation once again to calculate the stock projections for n+2 which again will be input to calculate the stock proj…
Kind regards!