UPDATE 1-TV audience for Biden inauguration tops Trump's viewership four years earlier

(Recasts with data from Nielsen)

LOS ANGELES, Jan 21 (Reuters) - Roughly 40 million people watched live coverage of Democrat Joe Biden's inauguration as U.S. president on six TV networks, according to Nielsen data released on Thursday, a 4% increase over the number that tuned in for Donald Trump's swearing in four years ago.

The figure covers the 30-minute span starting at 11:45 am on Wednesday, when Biden took the oath of office and delivered his inaugural address from the U.S. Capitol. It includes the audience on broadcasters ABC, CBS and NBC and cable channels Fox News, CNN and MSNBC.

In 2017, about 38.3 million people watched Republican Trump's inauguration and speech on those networks.

Biden became the 46th U.S. president on Wednesday in a ceremony that included performances by Lady Gaga, Jennifer Lopez and Garth Brooks. Kamala Harris made history as she became the first Black person, first woman and first Asian-American to serve as vice president.

The TV viewing figures do not capture people who tuned in via digital platforms such as Twitter, Facebook and YouTube that streamed the event live, or others who watched on TV at places outside of their homes such as bars and restaurants.

(Reporting by Lisa Richwine; Editing by Leslie Adler and Bill Berkrot)