We have a form request that members fill out to freeze their membership. The date only goes up to 2014 and we need to go to at least 2015.

How do we extend the years available on the form? Here's a link to the form http://www.jotform.us/form/23455981096160

You may add one of the Date Picker widgets instead of the Birth Date Picker:

Using one of them will allow the user to select dates beyond 2014. Please check my example form here. Let us know if you have more questions we will be glad to assist you.