Not sure if this is the right place to ask.
Currently interning at a large corporate gig and I was assigned with a task to forecast individual AP (monthly) from suppliers but cannot figure out how to do it properly. The company already has a way they do it, but they want to try to make their forecasts more accurate so they gave me a shot at it.
I have access to almost any company info. I tried a de-seasonalizing method to forecast, but that didn't work as it cannot forecast AP accurately enough when I compare the results against actuals.