A method for generating a sales volume forecast includes receiving user input specifying a hypothetical asking price and a future date and accessing, for each of multiple past time periods, historical data reflecting a sales volume for an item over the past time period and a corresponding price difference between an asking price and a coinciding market price for the item, the price difference also being associated with the past time period. The method also includes determining a historical correlation for the item between sales volume and price difference between asking price and coinciding market price, accessing market data reflecting a future market price for the item associated with the specified future date, determining a price difference between the specified hypothetical asking price and the future market price for the item, applying the determined historical correlation to the determined price difference to generate a sales volume forecast, and providing the generated sales volume forecast for access by a user.