"My message is simple," President Obama said in his State of the Union address Tuesday night. He may have been speaking literally. Using the Flesh-Kincaid readability test, which employs a mathematical formula based on the number of words and syllables in a text's sentences to determine its reading level, the University of Minnesota's Smart Politics blog calculated that Obama's speech was written at an "8th grade reading level" — the fourth-lowest of any State of the Union since 1934. Here, a look at how that breaks down, by the numbers: 

Grade level of Obama's 2012 State of the Union address

Grade level of Obama's 2010 address

Grade level of Obama's 2011 address

Average grade level for the 70 presidential State of the Union addresses delivered orally since 1934

Average words per sentence in Obama's 2012 and 2010 addresses. His 2011 address averaged 16.8 words per sentence.

Rank of Obama's 2012 address, according to its grade level, out of the last 70 State of the Union speeches

Obama's rank among the last 13 presidents when it comes to the average grade level of their State of the Union addresses

State of the Union addresses since 1934 that were below a ninth grade reading level, including all three of President Obama's

State of the Union addresses since 1934 that averaged less than 17 words per sentence, including all three of President Obama's

Average grade level of John F. Kennedy's State of the Union addresses, the highest of the 13 presidents measured. His speeches averaged 23.8 words per sentence.

Presidents since 1934 who delivered at least one address at the 12th grade reading level: Harry S. Truman, Franklin D. Roosevelt, Richard Nixon, John F. Kennedy, and Dwight Eisenhower

Lowest grade level for any State of the Union address, delivered by George H. W. Bush in 1992. Obama's 2011 and 2012 speeches come in as the the second and third lowest, respectively.

Average grade level of George W. Bush's addresses

Average grade level of Bill Clinton's addresses

Grade level of Gov. Mitch Daniel's (R-Ind.) State of the Union rebuttal Tuesday night, notes Mollie Hemingway at Ricochet

Grade level at which the average American reads, according Robert Lehrman at Politico. Perhaps "Obama's simple language is in part a reflection of his audience," says Byron Tau at Politico.

Percent of Americans who approved of Obama's State of the Union address on Tuesday, according to CBS News

Sources: CBS News, Politico (2), Ricochet, Smart Politics