Since 2000, fatigue has played a role in about 20 accidents or incidents we've investigated, and 15 of those events involved the crew and pilots. A number of those events involved private airplanes. In the commercial sector, fatigue or fatigue management has played a role in five or six cases, and that's out of many investigations. However, in the rail transportation sector, we found that the fatigue factor has contributed in a higher proportion to incidents and accidents. That's why we included the fatigue factor on our watchlist for freight trains and not for air transportation.
