A week later, the “Barbenheimer” boom has not abated.

Seven days after Greta Gerwig’s “Barbie” and Christopher Nolan’s “Oppenheimer” conspired to set box office records, the two films held unusually strongly in theaters. “Barbie” took in a massive $93 million in its second weekend, according to studio estimates Sunday. “Oppenheimer” stayed in second with a robust $46.2 million. Sales for the two movies dipped 43% and 44%, respectably — well shy of the usual week-two drops.

“Barbenheimer” has proven to be not a one-weekend phenomenon but an ongoing box-office bonanza. The two movies combined have already surpassed $1 billion in worldwide ticket sales. Paul Dergarabedian, senior media analyst for data firm Comscore, call it “a touchstone moment for movies, moviegoers and movie theaters.”

“Having two movies from rival studios linked in this way and both boosting each other’s fortunes — both box-office wise and it terms of their profile — I don’t know if there’s a comp for this in the annals of box-office history,” said Dergarabedian. “There’s really no comparison for this.”