The years referred to for the lottery can be confusing, so please read this to understand what they mean.
Let us give you an example.
The 2013 application submission period was from 1 of October 2013 through 2 of November 2013.
The 2013 application is referred to as the 2015 Diversity Immigration Visa Program (DV-2015).
The reason it is called the 2015 (DV-2015) program because successful applicants will receive their visas (Green Card) during the 2015 fiscal year, which runs from the 1 of 2014 to 30th of September 2015.
We hope this clarify the confusion.