Bud Light sales are still lacking flavor.

Anheuser-Busch InBev's (BUD) Bud Light volumes crashed 28.1% year over year for the week ending Aug. 13, according to new data from Circana and Evercore ISI on Tuesday. Bud Light has seen annual volume declines of more than 28% in each of the last four weeks.

The lone positive: Volume declines have improved from a 32% drop at the height of the controversy surrounding the brand for the week ending July 2.

The Bud Light uproar started after transgender influencer Dylan Mulvaney created an Instagram post during the March Madness basketball tournament endorsing the light beer.

Following the post on April 1, AB InBev saw Bud Light sales trend lower through April. The declines appeared to accelerate following an April 3 video from musician Kid Rock, which spurred a wider boycott by many on the right.

To try and stem the sales weakness, Budweiser offered US consumers in most states a rebate of up to $15 on a 15-pack or larger for July 4. And industry experts have pointed to additional discounts on Bud Light since July 4.

But those efforts have largely fallen flat.

The sales pressure has stretched well into the peak summer drinking months as the controversy has continued to play out on social media and in national headlines.

AB InBev has used the challenging sales moment to lower its costs. Earlier this month, it inked a deal to sell eight of its beer and beverage brands to cannabis player Tilray. The brands being sold included notable names such as Shock Top and Blue Point.

Analysts are speculating if more cost cuts are needed given the uncertain outlook for Bud Light.

"Continued weakness begs the question of whether Anheuser-Busch InBev and/or its distributors will have to make significant structural changes to reduce their cost basis if trends don’t improve over the next few months," Evercore ISI analyst Robert Ottenstein wrote.

Anheuser-Busch InBev stock has fallen 7% in the past six months as the sales declines persist. The S&P 500 has advanced nearly 10%. Meanwhile, Molson Coors (TAP) shares are up 17% while Corona maker Constellation Brands' (STZ) stock has gained 15%.

Brian Sozzi is Yahoo Finance's Executive Editor. Follow Sozzi on Twitter @BrianSozzi and on LinkedIn. Tips on deals, mergers, activist situations, or anything else? Email brian.sozzi@yahoofinance.com.

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