President Obama's State of the Union address attracted about 33.3 million television viewers Tuesday, the ratings tracker Nielsen announced Wednesday. It's the lowest total for a State of the Union speech since Bill Clinton in 2000 and continues a trend of declining viewership for the annual address to Congress.

That said, it's not much of a drop from last year's speech -- Obama's previous low -- when the president attracted about 33.5 million viewers for a 21.8 rating. The rating tracks the percentage of households that tuned in. Obama's rating this year was 20.7, Nielsen said.

State of the Union television ratings have been declining during the past three presidencies. As Dante Chinni recently wrote in the Wall Street Journal:

Last year, President Obama hit his personal rock bottom in ratings for a State of the Union address. About 33.5 million people tuned in for the speech, the lowest number since 2000, when about 31.5 million watched President Bill Clinton’s SOTU swan song.
But Mr. Obama’s numbers were actually worse than that. If you go by household ratings — the percentage of U.S. television households that tuned into the speech at any given moment — last year’s SOTU garnered a score of 21.8. That was the lowest in the last 20 years of data, even worse than 2000’s 22.4. (Household ratings offer a better comparison of viewership than raw viewer numbers because they take into account changes in the number of TV households.)

So is it fair to conclude that television ratings correlate to quality of a president's speech or how the public thinks about his agenda? Not necessarily. As Chinni noted, there are now many more ways for people to get news about the speech than there were in the past. It was also live-steamed widely online.

Even if you were not watching it, you could follow it blow by blow on social media tools like Twitter. If you missed it all live, you could catch up quickly by reading the flood of analyses that poured in instantaneously.

There is also more competition within the universe of television. Sure, more networks are covering the speech. But more networks are offering other programming, too.