• New Nielsen data suggests that "The Rings of Power" is struggling to attract a young audience.

• A third of the audiences for both "Rings of Power" and "House of the Dragon" is watching the other show.

• Both shows have more male viewers, Nielsen said, unlike the "vast majority" streaming content.

Two big-budget fantasy shows airing at the same time, HBO's "House of the Dragon" and Amazon's "Lord of the Rings: The Rings of Power," have invited comparisons, like viewership numbers.

Nielsen released new data Thursday that pulls the curtain back slightly on who's watching each show, in the US at least.

68% of the audience for "House of the Dragon," the "Game of Thrones" prequel, is concentrated in the 18-49 age group, according to Nielsen.

But "The Rings of Power" is struggling to attract younger viewers. It leans older, with 71% of its audience over 35 years of age.

Nielsen said that both shows have more male viewers, which it said "runs counter to the vast majority of streaming content."

Notably, large swaths are watching both shows: 34% of "The Rings of Power" audience also watches "House of the Dragon," and 34% of "House of the Dragon" viewers also watch "Rings of Power."

As far as how much viewership each show is racking up, they're close.

"Rings of Power" was watched for 988 million minutes the week of September 12 through September 18. It slightly edged out "House of the Dragon" on Nielsen's latest viewing chart, which was watched for 960 million minutes in that time frame.

But the streaming chart only includes "House of the Dragon" viewing on HBO Max. The show also airs on the HBO cable network, which Nielsen said would add 210 million viewing minutes to its total, bringing it to 1.17 billion minutes — more than "Rings of Power."

It's not a perfect comparison, though. Nielsen's data this week didn't break down how much the new episodes of each series accounted for its viewing minutes. Nielsen's rankings also measure Mondays through Sundays, and "House of the Dragon" airs new episodes Sundays at 9 pm — a limited window.