From Lincoln's famous “fourscore and seven years ago” to Roosevelt's iconic line “the only thing to fear is fear itself,” the White House has been inhabited by some pretty eloquent orators over the centuries. However, the current crop of presidential hopefuls appear to fall well below the mark set by some of their predecessors, according to a new study that suggests that the linguistic complexity used in campaign speeches is comparable to the reading level of a middle school student (grades 6 to 8, covering ages 11 to 14).

To conduct the study, researchers from the Language Technologies Institute at Carnegie Mellon University analyzed transcripts of recent speeches by five presidential candidates, and used a “readability model” to assess their “lexical contents and grammatical structure”. According to the sophistication of the vocabulary and syntactic organization of these addresses, the researchers were able to ascribe each speech a “reading level” corresponding to a particular grade within the American education system.

Assessing the announcement of candidacy speeches made by Hilary Clinton, Bernie Sanders, Donald Trump, Marco Rubio, and Ted Cruz, the study authors found that Clinton and Trump used the least advanced vocabulary, comparable to a grade 8 level, while Sanders utilized the most complex terminology, speaking at a grade 10 to grade 11 standard. Grammatically, Trump’s address was the most basic, with a linguistic structure similar to what one would expect from a grade 5 student.

Although Clinton’s choice of words was among the most rudimentary during her announcement of candidacy, she was also found to have the highest level of “standard deviation,” which reveals the degree to which candidates change their vocabulary between speeches. This flexibility may indicate a higher capacity to tailor the linguistic complexity of her discourse in accordance with her changing audiences.

The study authors also compared the lexical intricacy of present candidates with a selection of past presidents and found that, on the whole, Ronald Reagan used the most advanced words while Donald Trump’s vocabulary was the least developed. Grammatically, Lincoln’s addresses were the most sophisticated, reaching a grade 11 level, while George W. Bush’s speeches were the most primitive.