I believe that there is a misunderstanding of this article based upon a typo error.

The increased incidence of als in the Gulf War is two times or 200 percent over members of the military that did not serve in the Gulf War theater of operations.

Another study which included all members of the military going back before WWII showed that if you served in the military you are 1.6 times more likely to develop ALS than people who never served in the military.