Google has added a new type of notation to their Product Listing Ads (aka shopping ads), this time allowing retailers to add a notation when the price of a product has dropped by a certain percentage.

They are being displayed for Product Listing Ads that appear both above the search results and in the right sidebar as well, alerting searchers to the price drop.  It is not clear if there are any rules as to when the percent price drop can be added, such as if the retailer must actually reduce the price by that amount within the ad settings.

Here is another example for:

Google has been testing many different ways of displaying Product Listing Ads.  We have seen them trying out a price comparison feature, a large knowledge panel / PLA hybrid ad, and various annotations within the ad unit, not to mention the new PLA Buy Button that Google recently launched.