For example, their forecast for the first item in the table was 100 units, but it unfortunately only sold 26 units. However, with the last item listed, they sold 341 units but could have sold 569 units if they had ordered enough inventory. For the next catalog, they have an item for which they forecast demand to be 400 units. Suppose they will use that forecast along with the data in the above table to choose a normal distribution to model demand for this product. What standard deviation should they choose? (Keep the answer as an integer.)