Coca-Cola's stock fell in the days following a news conference in which Ronaldo replaced the company's products with a bottle of water. However ...
There's no real indication that Ronaldo's drinking habits impacted these stock changes, given that the company's stock started falling before this news conference.
On June 14, 2021, Portugal soccer star Cristiano Ronaldo sat down for a news conference to discuss his team's upcoming match against Hungary in the 2020 UEFA European Football Championship. Before Ronaldo took questions, he took the two Coca-Cola bottles that were left out for him, moved them out of frame to the side of the table, then held up a bottle of water and said, "Agua."
As this video went viral, a number of outlets reported that Ronaldo's Coca-Cola snub had cost the company billions of dollars. The exact cost of the snub varied from outlet to outlet, but the general claim was that it cost Coca-Cola between $4 and $5 billion.
Here's an excerpt from The Guardian's report:
Cristiano Ronaldo snub wipes billions off Coca-Cola’s market value
Cristiano Ronaldo’s removal of two Coca-Cola bottles during a press conference at the European Championship has coincided with a $4bn fall in the share price of the drinks company.
The Portugal captain is a renowned health fanatic and made it clear what he thinks of the carbonated soft drink. The 36-year-old shifted the bottles of Coca-Cola away from him during a press conference in Budapest on Monday in the prelude to his country’s Group F game against Hungary.
[...]
Coca-Cola is one of the official sponsors of Euro 2020. The company’s share price dropped from $56.10 to $55.22 almost immediately after Ronaldo’s gesture, a 1.6% dip. The market value of Coca-Cola went from $242bn to $238bn – a drop of $4bn.
While Coca-Cola's stock truly fell after this news conference, there was no indication that this drop was entirely (or even in part) caused by Ronaldo's preference for water. In fact, Coca-Cola's stock was already falling by the time that Ronaldo snubbed Coke products in favor of water.
Coca-Cola's stock price closed on Friday, June 11, at $56.16. At 9:30 a.m. shortly after the market opened again on Monday, the company's stock had fallen to $55.35. Ronaldo's news conference hadn't even started by this time. After Ronaldo's news conference (held at 3:45 p.m. Central European Time (or 9:45 am CST according to Sportico), Coca-Cola's stock briefly rose and then dropped again.
It's certainly possible that Ronaldo's endorsements (or disapproval) of Coke products could temporarily influence the stock market, but a few other facts should be noted.
For one, while a $4 billion stock drop may sound like an absolutely devastating turn of events, this really isn't a major story for Coca-Cola. The company has seen a number of similar drops and rises over the last year, and those changes had nothing to do with Ronaldo. As of this writing, Coca-Cola's stock is up about 15% from where it was at this time last year:
Furthermore, Coca-Cola's stock is not based purely on sales of their most well-known product, Coke. While Ronaldo may prefer water to soda, Coca-Cola has a large portfolio that includes a variety of products, including the water brand Dasani.