Dynamic Year Prompt in Cognos 10.2.1

Hello everybody,i’m searching for a solution to my new problem.

I have a report with a list and a value prompt in this page.I have no prompt page.
My prompt is filled with year data (2013,2014…) and i want that my report runs with a default dynamic year for value prompt.
The value and the display on my value prompt will have to be set to this default value.
the default value will be current year if it is present in prompt values otherwise the prior year…so if 2014 is present in prompt values the default will be 2014 else 2013…

i have read many post but none is correct or suitable to my situation…(some old javscripts for cognos 8 or 10.1.) and some with prompt page.

thank you for your time and for your
and sorry for my poor english.
i hope that i have been clear in my request.

Bye