Posting new PDF. How to Keep Google Happy?

[nabarro]

Posting new PDF.  Is there anything beyond maintaining the PDF metadata, filename and URL I need to do to keep its current top ten search ranking on Google for a specific generic noun which it currently ranks for? Many thanks ahead of time for your help.

[webestate]

What is the PDF about?  Just need to drive traffic to the PDF via social media, link building, basic on page seo.

[nabarro]

The PDF explains the economy.  Whilst I am not trying to actively drive traffic to the document at the same time I do want to actively prevent the document from losing its ranking.  Thank you