According to Nielsen 41,800,260 million viewers watched Ronald Reagan’s 1981 inauguration compared to 37,793,008 for Barack Obama’s.
Nearly 37.8 Million Watch President Obama’s Oath And Speech
Nearly 37.8 million Americans watching at home viewed President Barack Obama’s oath of office and inaugural speech between the hours of 10:00 a.m. and 5:00 p.m. ET on January 20, 2009. This is the most viewed inauguration since the record of 41.8 million viewers who watched Ronald Reagan’s 1981 inauguration.
This is the first inaugural since Nielsen began tracking time-shifted viewing, and this year’s data is based on Live + Same Day, meaning incremental viewing during the same broadcast day is included.