You were and are wrong. Your numbers have been challenged. Even IF true they offer no explanation as to why the South started the Civil War.
They have been called wrong. They haven't been shown to be wrong. As I mentioned before, you've conceded 60% of all exports were from the South, and you were only counting cotton. You are ignoring the other 13% from the South consisting of Sugar, Hemp, Molasses, and Tobacco.
Even IF true they offer no explanation as to why the South started the Civil War.
Well that's because the South didn't start the Civil War. If you want an explanation for that, you will have to look to the fact that Lincoln sent a fleet of warships with orders to attack them. (or did you even know about that?)
The South wanted independence because they would see an immediate economic benefit from gaining independence, because most of that European traffic to New York would have moved to their ports.
Lincoln started the civil war because New York would not sit by and take such losses, and the Federal government would also be out a lot in revenue that would have to be made up by further taxing the North.
Now you may come along and say "Oh! but the moral imperative of "Slavery"!
I'm a cynic. Show me a fight involving large quantities of money, and I will peg that as the cause over concerns about the welfare of people they hated anyway.