You can check it here cb-analytics.com or nichejunky.com. They can provide you with historic data. But I am not sure if you can configure the period ...
Yes, these are free tools, but you can't configure the time period. There are 2 good paid tools - affiliate elite and keyword elite by Brad Callen. Try either of them preferably keyword elite, you can get great historical and keyword related data.
It is funny that when we look to the NEW business ventures and opportunities on the Internet we still get bogged down in the OLD ways of researching and analysing data. In the past we have made our decisions based on Historical data that may be years old, In the NEW era we now look more toward the future, and the products POTENTIAL. The Modern marketer is more willing to take a gamble, those that are careful and scared to fail look to the historical data to prove to themselves that they can do it. ( hey if 100 people got sales last month I'm sure to get some this month) Once you set up a system that you are confident with, Historical data means Nothing. Unless it is your own data so you can analyse the success failure of certain areas of your own Marketing. The Modern Looks forward, a product can come and go in 6 months, 6 months historical data means ZERO. To get a good idea we need to go back 1-2 years or more, Most of the products we are promoting have not been around that long. And if they have the Opportunity is over except for a VERY small quantity that maintain Long term success. Sorry Got carried away. Forget the Past, Look to the future. One dumb Aussie
it is important to be familiar with the past of a product, though it has a little history. thank you.