Techniques are disclosed for advantageously forecasting an inventory of a product having a particular duration (e.g., video content). The technique can include determining the particular configuration (e.g., maximum number of impressions, maximum amount of time permitted) of breaks identified within an impression log. Based on the number of breaks and the configurations of the breaks, the technique can forecast a future inventory of the product. In some implementations, the disclosed technique can identify an amount of a previous break that was not filled with video content. These forecasts can enable product sellers to better communicate with their customers, negotiate supply contracts, price their products, plan for business operations, etc.