Pizza Hut and KFC same-store sales decline, contributing to Yum Brands' revenue shortfall.

• Yum Brands reported revenue that fell short of expectations for the second quarter.
• KFC and Pizza Hut both saw their same-store sales shrink.
• The only restaurant in the company's portfolio that reported same-store sales growth is Taco Bell.

On Tuesday, both Pizza Hut and KFC reported declining same-store sales, resulting in revenue that fell short of expectations.

Shares of the company rose less than 1% in premarket trading.

Based on a survey of analysts by LSEG, the company's reported results differed from Wall Street's expectations.

• The adjusted earnings per share is $1.35, which falls short of the expected $1.33.
• Revenue: $1.76 billion vs. $1.8 billion expected

Yum's second-quarter net income decreased to $367 million, or $1.28 per share, from $418 million, or $1.46 per share, in the previous year.

Excluding items, the company earned $1.35 per share.

New restaurant openings led to a 4% increase in net sales to $1.76 billion, while Yum's same-store sales fell 1% in the quarter, with Pizza Hut and KFC reporting declines of 3% each.

Despite KFC's growth in China, its U.S. restaurants still experienced a 5% decline in domestic same-store sales, while its overall international sales fell 3%.

In the US, Pizza Hut's same-store sales decreased by 1%, while its international same-store sales declined by 4%.

Yum's flagship restaurant, Taco Bell, experienced a 5% increase in same-store sales in the latest quarter. Its primary market is the U.S., where its affordable pricing has helped it endure the economic downturn.

By the end of the year, Taco Bell drive-thru lanes in hundreds of Yum's U.S. restaurants will have artificial intelligence rolled out.

This story is developing. Please check back for updates.