I should have explained that this is an assignment I have been given by my uni professor and I need to do as it is set out for me.
I have tested it and when i -1 from year, it comes up right. (not sure why I need to do that)
Using Prompt, is how I am being shown at uni, it could possibly be that when I have learn this first stage, I may be shown a different way.
Thank you for your comments I will bring these things to him and find out why I am learning this way.