Upgrading to NIS 2014

Ok I am going to now upgrade from NIS 2012 to NIS 2014. As I always do, I will purchase the NIS 2014 from the store and install using the disk. I know I will have to run live update several times , but it usually only takes no more than 3 update runs
I just like having the disk

So my question is
Can I install NIS 2014 over my current installation of NIS 2012?
I did do 2012 over 2011. But I have skipped over 2013 so I don't know if an over the top install of 2014 over 2011 is ok to do

or do I need to remove 2012 first and then install 2014?