Following the pilot-test rollout of a Whopper made with the vegetarian-friendly Impossible Burger, locations in Burger King’s St. Louis test market reportedly exceeded the restaurant’s foot traffic national average by 18.5 percent in April.

The data comes from inMarket inSights, which looked at location data in March prior to the Impossible Whopper test in April, CNBC reported.

City locations brought in 16.75 percent higher foot traffic in April compared to the average in the month before for all Burger King locations in the U.S. At the beginning of April, the Restaurant Brands International chain said it was testing the vegetarian-friendly Whopper version. And, prior to the end of the month, the brand said it would roll out the burger later in the year nationwide. The company has brought the product to three additional cities since then.

Bank of America Merrill Lynch Analyst Bryan Spillane said in a research note about Beyond Meat, which the article described as Impossible Foods’ major competitor, “These next generation plant-based alternatives are in position to disrupt the meat category in a similar fashion that plant-based milks disrupted dairy and energy drinks disrupted caffeinated beverages.”

The news comes as Impossible Foods, which makes the Impossible Burger, said it has notched a $300 million investment in its newest funding round.

The raise by the firm, which is backed by celebrities such as Serena Williams and Katy Perry, highlights the growing appeal of plant-based foods that aim to have a meat-like taste. The California-based company has brought in more than $750 million with the newest funding round.

Impossible Foods Chief Financial Officer David Lee, however, said per reports earlier in May that the company is not rushing to go public. “We believe in self-reliance,” Lee said. “Being ready to go public is a priority for the company because we need to be operating at the highest level of rigor.”