Despite being labelled a flop, Coca-Cola Amatil's chief is still standing by Coke Life's sales performance two weeks out from the company's half-year results. The lower-calorie cola in a green can was meeting near-term expectations of just one to two per cent of "brand Coke" sales, managing director Alison Watkins said on Thursday.She wouldn't go into details ahead of the release of official results but said it was "definitely" capturing Coke's target market of 18 to 34-year-olds. "Near term our expectations based on the experience from other similar markets is it will probably be about 1 to 2 percent of brand Coke," she said. "I think it will grow because the natural sweeteners are continuing to improve so we'll be able to reduce the calories over time and also as consumers continue to think more actively about the choices they want to make."

The confidence came despite estimates from analysts Credit Suisse that the new product sold just 7 million litres in its first five weeks, half of Vanilla Coke and less than a quarter of Coke Zero's launch effort.

But Ms Watkins revealed one of her former colleagues was an outlier, chugging down 18 cans a day on his own. Coke Life, with its Stevia natural sweetener promising 35 per cent less sugar, was an attempt to reverse falling Coke sales. The latest sales figures from The Coca-Cola Co, CCA's parent, showed still beverages such as water and iced tea were growing much faster than sparkling drinks.

Ms Watkins touched on these challenges in a speech to a business leaders' forum in Brisbane on Thursday, along with revealing herself as a Coke Zero drinker. "We often say that we live in challenging times and it's true," she said. "It's definitely true for us and the team at CCA. "The economy is challenging, consumer confidence is relatively low.

People's tastes are definitely changing. "But while it's true it's definitely not a lament and we don't use it as an excuse." She was quick to push her company's focus on diversification into non-cola markets at a business but said she couldn't see the day where Coke wasn't CCA's biggest selling, flagship product. "Coke is a must-have brand and I believe that will always be the case," she said.