Seeking to bolster sales after falling behind its main competitor Coca-Cola Co. in recent years, PepsiCo Inc. has started to tweak the formula of Diet Pepsi, the Associated Press reports. The company is adding the sweetener acesulfame potassium to its diet soda, which already includes the artificial sweetener aspartame. In 2012, Diet Pepsi lost a small market share and remains the seventh best-selling carbonated drink. Diet Coke ranks number two.

Over the past couple of weeks, cans of Diet Pepsi across the U.S. have started listing both ingredients, a pairing that the AP notes is commonly found in newer diet sodas. After declining to confirm surfacing reports that the company was testing out new sweeteners this past summer, a Pepsi spokeswoman confirmed that the new formula began hitting store shelves in early December.

An official statement released by Pepsi this past week also noted that “a very small amount” of acesulfame potassium is being added “to ensure consistency with every sip.” It appears that the company is going out of their way to reassure the public that any changes to the drink will be minimal and virtually unnoticeable, ahead of a new major ad campaign. Calm down, people. We’re not quite at New Coke or Crystal Pepsi alert level yet.

But while we’re at it, remember Crystal Pepsi? You can buy it on eBay! And remember the commercials?

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