Typical abandonment rates and what to do about it

[itHighway]

First let's agree on terms. By "abandonment rates" I mean
people that open up a shopping cart and then leave it without
completing a transaction.

I have been trying different strategies to try to decrease
abandonment rates without much success.

Our products run from $5 to $5000, we get about 500 on-line
orders a month and another 200 by phone. We average
$200k in sales per month.

So what are typical abandonment rates?

best regards
wiz