How can I download my order shipping history data?

Presently I offer calculated shipping for domestic orders beneath $100 and free shipping for those above. I am considering replacing calculated shipping with a flat rate to reduce the "how much is shipping " question and to reduce abandoned carts. I would like too look at the #'s to test the strategy and set the rate. Is there some way to download my order shipping history for the last couple of years? It does not seem to be available in the preset download. Thanks in advance.