Products can be tagged as ‘Forecastable’ during the product set-up. When products are tagged, they well appear in your Product Forecast tab.
To make a product forecastable:
Go to the Suppliers tab
Locate the appropriate supplier and open their product list by clicking on the Products text link.
Click the Edit button next to the product you wish to add to your forecaster.
Scroll and find the ‘Product Tags’ section
Click the ‘Forecastable’ option in the drop-down menu.
When you're happy with your settings, don't forget to click Save Changes at the bottom of the page.