U.S. American vs United Statian

U.S. American

adj

  • American 

noun

  • A person from the United States of America. 

United Statian

adj

  • Pertaining to the United States. 

noun

  • A citizen or inhabitant of the United States. 

How often have the words U.S. American and United Statian occurred in a corpus of books? (source: Google Ngram Viewer )