Document library columns going blank with each new version.

Hello,

I have a Document Library on our SP2010 site that we will be using as a repository for support documents, and some of them get updated often enough. The problem is that every time a new version of a document is uploaded, the columns that don't get automatically filled such as the title are blank again. For example, we have an APP CODE column that has a value that almost never changes with each document, and when we upload the new version we either leave it blank which erases that previous field, or type it all over again.

Is there any way to keep the text from previous versions unless manually edited when uploading a new version? It'd be great if those fields can get populated with previous data instead of going blank every time.

Thank you!
Nick