To calculate the overall star rating and percentage breakdown by star, we do not use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
I was extremely disappointed with the quality of the sparkling water that arrived. There was no sparkle at all per se. Even opening a fresh bottle gave only a very tiny psssst. Luckily, amazon refunded the full amount for this item. Thanks for being prompt!