‘Man overboard’ problem

Brad Tuttle has a Time article about a mystery:

It appears as if the number of cruise-ship passengers who jump, fall, or otherwise end up in the ocean is regularly underreported. Perhaps four times as many passengers as official reports would lead the public to believe actually head overboard.
A recent report in the Miami Herald calls upon the research of Ross Klein, a sociology professor at Memorial University of Newfoundland, who, over the years, has pursued the dark side of the cruise industry as his personal white whale. Klein operates a site called Cruise Junkie, and he has chronicled all sorts of questionable cruise practices, especially concerns about crime and safety.
Over the summer, Klein testified before the Senate Commerce, Science, & Transportation Committee, where, among other things, he told officials that crimes on cruise ships were drastically underreported:

In practice, there are many crimes that are either not being reported to the FBI, or which the FBI chooses not to make available to the American public. Take as just one example the fact that for one fifteen-month period the FBI reported a single case of sexual assault on Norwegian Cruise Line; however records disclosed in discovery indicate the number was actually 23.

Soon after the hearings, cruise lines began releasing more information about crimes that have allegedly taken place on their ships. In August of 2013, for instance, The Associated Press reported that Carnival, Royal Caribbean, and other cruise lines had voluntarily made crime data public on their websites.
“Man overboard” situations are not necessarily crimes, however, and the exact number of such incidents remains something of a mystery. In written testimony over the summer, Klein explained to the Senate committee that “the number of people going overboard from cruise ships is significant: between 20 and 25 a year since 2009.”
Yet according to the Miami Herald, when the major North American cruise companies released their data this summer, there were only seven cases listed under the category of “missing US national” occurring between October of 2010 and June of 2013. Klein claims that, in fact, thirty “man overboard” incidents took place during this time period. Miami Herald investigators were able to confirm 28 of these incidents with the cruise lines involved.
So why is it that only seven “missing US national” cases were made public? Well, not every “man overboard” situation winds up as a “missing US national.” A handful of the people who wound up in the ocean were saved, and therefore they aren’t missing. Also, as the Herald explained, there are several “man overboard” scenarios that don’t make it into the official count of “missing US nationals”:

Crew members or passengers from other countries, survivors who are rescued, people whose bodies are recovered, and those sailing on foreign fleets abroad aren’t reported publicly in any official tally, which makes the number of man-overboard incidents difficult to pin down.

Klein has estimated that there have been more than two hundred “man overboards” on cruise ships since 2000. That’s a miniscule figure in the grand scheme of how many passengers board cruise ships. According to the Cruise Lines International Association, there were 7.214 million cruise passengers in 2000, and by year’s end, there will have been 17.6 million passengers hitting cruise ships in 2013.
Still, because anytime a cruise passenger winds up in the ocean it’s a potentially deadly situation, the public understandably wants full and honest disclosure. Failure to do so “makes it appear as though they have something to hide,” Klein told the Herald. “You just wonder, because if it’s as infrequent as they say it is, no one’s really going to take note of it.”

Rico says that, on his recent excursion down the Rhine with his ladyfriend, he worried about this; it's cold and dark out there at night, and no one may hear the splash...