There are four components to the forecasting process. The first one is to input historical data. Now this may be published, it may be publicly available or alternatively it may be private and provided to you by the management of the company you're looking at. This leads us very nicely into the second component. We will build ratios and statistics based on the historical data, so for instance, we may have a couple of years of historical sales and we see that sales have been growing by 5% every period. That would be my ratio or statistic the 5% increase. This means that I can now go looking for key links or performance drivers between some of the numbers. That links very nicely into the third component which is making future assumptions. If I've seen that my historical sales have gone up by 5% every period I may assume that my future sales will go up by 5% as well. So history is the first place to look for your future assumptions, but you may find other inputs as well. You may have some industry research which you think is going to impact on your company. You've now got 5% being your assumption for the future increase in sales you now just need to actually forecast that sales figure. So if last year sales were 100 step 4 would say that this year's sales would be 105.