This posting is the second part of a series focusing on 2008′s top 100 movies, ranked by total U.S. box office gross. As many of the top earners like The Dark Knight, Iron Man and Wall-E received favorable reviews I wanted to check out the link between a ‘quality’ movie and box office success.

To represent the overall opinion of movie critics I used a well-known proxy: Rotten Tomatoes (RT) Scores. RT Scores are a rough average of the good or bad reviews a movie receives from ‘accredited media outlets and online film societies.’ An RT Score of less than 60% is deemed to be ‘rotten’ while anything at or above is ‘fresh.’ Plotting these RT Scores against the total U.S. box office for 2008′s top 100 presented the following graph:

Visually the accumulation of points along the bottom looks like a small hill without much direction. Certain outliers lie above this crowd but don’t really portray any trend. Mathematically these plotting has a correlation of 0.448, which indicates a very poor relation between critical reviews and box office.

I then decided to look at per-theater averages, since it’s commonly used to fairly compare movie performance. Plotting the RT scores against the per-theater average box office for the same movies yielded slightly different, but still inconclusive results. The correlation of this plot is slightly less, 0.426.

After seeing this similar study of RT Scores in 2007, I then decided to run the analysis based on average per-theater results for the two categories, ‘fresh’ and ‘rotten’ movies. Plotting the average weekend per theater performance during the first eight weekends provided the following trend lines.

What emerges here is a distinct box office performance difference between movies who have been reviewed well or poorly. On average, during the first eight weekends in theaters, ‘fresh’ movies earned about 84% more per theater than ‘rotten’ movies. Of course, as in the case of all averages there were various exceptions. ‘Rotten’ movies like Twilight and Hancock outperformed many movies on a per-theater basis, earning above the $15,000 per theater during the first weekend, above the ‘fresh’ average.

What is also interesting is how much these averages change between weekends. ‘Fresh’ movies do drop less during the second weekend, but then follow a slightly higher drop off during the next four weekends. Perhaps what is going during the second weekend is that positive critical reviews, and possibly positive word of mouth, is giving these movies an additional boost, whereas with ‘rotten’ movies negative commentary is circulating.

In any case I believe this posting demonstrates a strong link between good movies and box office success. Tomorrow I will be looking at the production budget and ‘profits’ of these movies.