Adjusted totals are a slippery slope....especially the further back you go.
40 years ago, people only had one way to consume movies; going to the theater.
It's been a gradual process of more and more ways to consume a movie; VCR, cable, DVD/Blu-Ray, internet sales, streaming, etc. People consume most movies any way other than going to a theater these days. Revenue is coming from a lot of sources, not just the Box Office gross.
Comparing the Hobbit trilogy to the Lord of the Rings trilogy and adjusting is mostly fair, as they are only about 10 years apart.
But adjusting Gone with the Wind with The Force Awakens is apples to f@cking oranges.