Why is the newer edition of this book cheaper than the old?

[mindheavy]

Larson Calculus

Both editions appear to be the complete book (covering all calculus topics through vector calc)

The newer 10th edition is less expensive than the older edition. I'm wondering this because I'm about to buy one and I have a choice of either edition as far as my class goes. Just seems weird that the older one costs more.

9th Edition
10th Edition

 

[Office_Shredder]

That's a bit bizarre. Checking barnes and noble
http://www.barnesandnoble.com/w/calculus-ron-larson/1116747036?ean=9780547167022
http://www.barnesandnoble.com/w/calculus-ron-larson/1100529887?ean=9781285057095

The 9th edition had a list price of 293 dollars and the 10th edition had a list price of 266 dollars. The first conclusion is you should go ahead and get the 10th edition from amazon because apparently it's a hundred dollars off what you'll get in a store (which is insane, the textbook market is ridiculous)

The rest of my post is pure speculation - I would imagine that books may be discounted at the start of a print run compared to later runs simply because they make/sell more of them so they get an economy of scale. Furthermore most of the price discrepancy on Amazon is because one book is heavily discounted to the list price compared to the other, which might be because they don't discount out of print books compared to how much they are willing to discount in print books