This has some more information: http://www.ninds.nih.gov/disorders/amyotrophiclateralsclerosis/detail_ALS.htm#266944842 http://www.ninds.nih.gov/disorders/amyo

This has some more information: http://www.ninds.nih.gov/disorders/amyotrophiclateralsclerosis/detail_ALS.htm#266944842 http://www.ninds.nih.gov/disorders/amyotrophiclateralscleros... It references data in the OP.