What year is my motor?

I have a 15 hp evinrude. E15rcta. Serial #E0204335. What year is it? How do you tell and is there a web site for looking them up. Thanks Mike
The motor is for sale.

i think it is the last 2 digits, mabye only on some, but i dont know if its that old or not

I think I figured it out but the moon is not in the right phase to know for sure. It is all most that complex.
Here goes. You look at the model # and take the 5th and 6th letter. Place them above thesame letters in the word INTRODUCE and this will give you the year.
Example

T C = 83
I N T R O D U C E
1 2 3 4 5 6 7 8 9
I believe this is right but hope it is not. Who and why would they come up with something like this?
I see my example is not going to come out exactly the way I wanted it to but I hope you get the idea