Advertisements and Percents of Change

Is this the best deal?  What discounts are being offered?   The advertisements online and in print are full of discounts that can be beneficial to savy shoppers.  
For example, Target's website shows discounted prices on movies.   http://www.target.com/sb/entertainment-movies/-/N-5xsx0Z5zktyZ5zja2.  One movie that is adverstised is Harry Potter and the Deathly Hallows.  The original price is shown as $28.98, and the sale price is $12.99.  This can be estimated to be a 3/5 or 60% decrease in price.  The prices listed on the webpage make it is easy to find the percent decrease.  What other percent decreases are there on DVD's at Target?  Is there a better deal (more than 60% off DVD's at Target?  One way to find out is to compare the percent change.
If you'd like to learn more about percent change and spend some time playing a computer game, here's a weblink from The Percent Shopping Game.
http://www.mathplayground.com/percent_shopping.html