Consider the following data that identifies real gross domestic product (GDP) in comparison to the long-run trend of real GDP to answer the following questions: 
 Quarter Real GDP Long-Run Trend of Real GDP
 (billions of dollars) (billions of dollars) 
 1 4,000 4,000 
 2 4,160 4,120 
 3 4,326 4,244 
 4 4,413 4,371 
 5 4,501 4,502 
 6 4,591 4,637 
 7 4,499 4,776 
 8 4,409 4,919 
 9 4,673 5,067 
 10 4,954 5,219 
 11 5,252 5,376 
 12 5,376 5,537 
 In what quarter did this economy enter a recession?