Publish a counter on the webpage after the form is completed?

Publish a counter on the webpage after the form is completed?

I'm using a form as a way of collecting online pledges towards a goal.
 
--#1 --  Is there a way to post the number of people that complete the form to a webpage?
 
--#2 -- Is there a way to make this editable (meaning we collect pledges at events too and need to update the numbers manually as well.
 
Thanks in advance, I like you all.