evidence: Obama and his wife, Michelle, marked the history of American music during the latest installment of the PBS television program "In Performance at the White House." The president also noted the 50th anniversary of the National Endowment for the Arts and the Humanities. [...] Obama referenced one of the evening’s performers, Buddy Guy, who once said artists are singing about "everyday life, rich people trying to keep money, poor people trying to get it and everyone having trouble with their husband or wife." "Except me," Obama added. The audiences’ laughter filled the White House East Room, which had been transformed into a concert venue with an elevated white stage and blue spotlights.