Display monthly price while billing 1 year period

Hi there,

I am currently trying to place some virtual products(like support or software) in our webshop. Buying one of these means buying the service for one year. However, I would like to indicate the price per month with a short note that billing is for one year. This way the customer can understand what actual monthly cost is and the price is represented in a fair manner.
Of course, when it comes to payment, the customer is asked to pay the price of exactly one year (i.e. 12x indicated price).
Does anybody know a Plugin/Hook or something similar to arrange this?

Thank you so much and kind regards
Fabian