How Accurate is Counter History

Would be interested to know exactly how accurate the counter history is on the Admin screen.

I am UK based and had my site transferred over to US servers a couple of months ago.

The counter history has decreased from around 2500 - 3000 per day to 200 - 300 per day.

Can this be relied on?

I am getting mixed reports...some people tell me that its not a problem going to US servers but others say I should keep it UK.

I have indicated on Google Webmasters that my site is UK based.

I can't guage any change in sales as this last year has probably been my worst ever due to the economic climate.

The counter history has decreased from around 2500 - 3000 per day to 200 - 300 per day
What is your conversion rate - before & now

Sales per number of visits