TotalBuckets in Term Aggregation

I am using a Term Aggregation.
I want to limit how many terms/buckets (because I don't want to display all of them to the user) (so I set the size)
But I do want to indicate to the user when they are not looking at the full results - ie I want to be able to display "showing 20 of 240 results".

Is there a way of getting the total number of buckets/terms?