We used a model based on different parameters to estimate the total cost of a ship procurement program. We used it to determine, in retrospect, what the results would have been if we had used that method for the costs that are already known. As an example, we considered procurement programs that have already taken place elsewhere in the world. In certain cases, the costs are an additional 20%, in other cases the costs are negative, or -20%.
That is how we estimated our confidence interval. The cost estimates we show in our report are the midpoint of our estimates. Possibly, there may be an additional 20% or savings of 20%. Our model shows that midpoint, using the figures in the report.