How many total history records in your database? Why do you want to know?

select count(*) from conthist

Which contacts have the most history?

select company,contact,* from contact1 where accountno in
(
select top 25 accountno from conthist where accountno <> ''
group by accountno
order by count(accountno) desc
)

Obviously, if you'd like to see your top 50 or 100, just edit the "25" accordingly.

How many history entries, by user, last 30 days?

select userid,count(accountno) as Count from conthist
where createon > getdate() - 30
group by userid

Find out which salesreps are keeping active (or, at least, which salesreps are using GoldMine according to plan!)