[Plugin: Contact Form 7]Form submission counter

Hi,

I have searched google but havent been able to find a solution to this.

Does anyone know if there is a way (either by coding or plugin) to count the number of times a contact form has been submitted, and display the total on the forms page?

I have a site which offers a sort-of group buying option to customers, but rather than buying directly through the site (as the items are rather expensive) they join the items ‘group’ by submitting the form. The more people who join the group, the more discount we can offer. So, I want potential customers to be able to see how many other people are members of each ‘group’, to encourage participation.

EDIT: Forgot to mention, each ‘group’ has its own unique form, so a solution that counts all emails sent from Contact Form 7 wont work, it has to be based on each forms submition count.
Regards,

Dan