The movie Avatar overtook Titanic as the highestgrossing movie of all time. An article on Forbes.com notes that "the average ticket price in 2008 (Avatar was released in 2009) was $7.18, up 56% from prices in 1997 when Titanic was in theaters." The article states: "A look at domestic grosses (box-office receipts) adjusted for inflation shows a more realistic view of Avatar's performance." Why would adjusting for inflation show a more realistic view of Avatar's performance at the box office?