For years, Diet Coke has had growth in sales, making it the #3 beverage overall. Meanwhile, sales of flagship drinks like Pepsi and Coke have continually dropped as folks got more health-conscious. However, recently, Diet Coke has been hitting some rough waters, as noted by an article in The Atlanta Journal-Constitution:
Coca-Cola has counted on Diet Coke — the No. 3 soft drink in the country — to help make up for declining sales of its flagship Coca-Cola Classic as consumers turn away from traditional soft drinks toward everything from bottled water to energy drinks.
Sales of full-calorie Coca-Cola Classic and Pepsi Cola have retreated each year since 1998. But the diet versions had held strong — until recently. Diet Pepsi suffered an even larger slide than Diet Coke during the past two years, according to Beverage Digest.
Industry experts agree the decline is not an anomaly, especially at a time when people are increasingly concerned about the health affects of artificial sweeteners.
What's been interesting to note is that not only has Diet Coke been losing some market share to outside drinks (such as Glaceau's Vitaminwater or Pepsi's Gatorade), but there's been some internal cannibalism as well, in the name of Coca-Cola Zero. Zero has been doing pretty well for Coke, however it's been pulling sales away from both the flagship drink as well as Diet Coke. One wonders how many new customers Zero is pulling into the Coke fold that aren't being pulled from customers of other Coke products.
As this is Diet Coke's 25th anniversary, it's being given some new marketing campaigns, a refreshing in package design, and some other products in the brand to keep awareness up (such as Diet Coke Plus).
Even if sales are slumping a bit for Diet Coke, I don't see them giving up their #3 spot any time soon.