Here is total tickets sold for each SW movie: (Source: Boxofficemojo.com)
SW (1977) - 178,000,000
ESB - 98,000,000
ROTJ - 94,000,000
TPM - 84,000,000
AOTC - 53,000,000
ROTS - 59,000,000
Now putting aside rereleases and people knowing that the movie was coming to DVD in 6 months, no SW movie comes close to the original. In the summer of 77, everyone saw SW, not just the fans. You could recommend it to everybody cause it was a standalone movie. It wasn't about the Skywalker drama, or the Emperor plotting to take over, it was a simple movie of good vs evil, and it shows cause even ESB & ROTJ just equal as many people seeing the original, and they are still universally loved by the fans. The prequels you could see the dip, and as I said, the numbers are a little lower because of DVD coming out quicker, and the PT will never be re-released, but it is still not even close the the original, and substantially lower than the OT.
Pop Culture refers to a reference that any Joe Blow on the street will know, but doesn't necessarily have to like the subject.
For instance, President Reagan named a missile defense system to save our butts from Nuclear War after 'Star Wars'! Do you think he did it because he was a fan of the movies? No, cause every person in the US at that time new what that meant.
He called the Soviets the Evil Empire, and once said in a speech, "the Force is with us!" Everyone new what they meant, but Im sure they didn't run out and see ESB opening weekend.
In movies, bad guys are sometimes referred to Darth Vader, teachers are known as Yoda, and put two donuts on your ears and ask the person whose hairstyle that is? I guarantee they say Princess Leia.
The PT had none of these, and in fairness, that is how much a phenemenon the OT is, because most movies dont have ten million pop culture references. The Matrix has "Bullitt Time"
Alot of fans forget the impact of the original SW because it is titled Episode IV now, but at the time it transcended the summer blockbuster and movies in general. ESB moved the series to just SW fans liking it, and there is nothing wrong with that, just as the PT has brought in new fans, but as you notice the numbers decrease everytime. We may think the PT lovers audience is huge, but I am starting to have my doubts. Think how many of us seen the PT in the movies, some of us saw it twice, and most of us here don't like it or love it. And it still isn't up to the OT numbers, so I am starting to believe that the PT lovers may be alittle smaller than even I thought it was during this run of movies.