Pop Candy blog on the value of adjusting for inflation to get an accurate comparison of film box office.
The fact is, if you not only adjust for average ticket price inflation, but also factor in the percentage of Avatar's box office coming from higher ticket priced 3D screenings, on a worldwide box office basis, Avatar would need another $1.3 billion to beat Titanic's record (approximately the amount of Haiti's total expenditures in 2008 per the CIA's World Factbook) and $700 million more to beat Star Wars: Ep IV A New Hope.
Adjusting for ticket price inflation is no easy task. On older films you have to adjust up from rentals to box office, adjust each re-release separately and, when possible, factor in the impact of higher than average ticket prices (for roadshow or 3D pricing). And when foreign box office is such a big swing factor (which it is in the case of Avatar where it makes up about 70% of Avatar's total worldwide box office to date), there are more variables at play. Using an estimated $7.35 average ticket price in the U.S. for 2010, adjusting for a $9 3D ticket price on 70% of Avatar's domestic box office, adjusting 50% of The Birth of a Nation's domestic box office for an average $1 roadshow ticket price and using U.S. average ticket prices to calculate foreign box office - the graphs above more accurately reflect the phenomenal success of Avatar compared to other cinema giants. It's great but it's not yet even in the Top 10!