Actually, that table is a bit out of date. Isabel reached Cat 5 two years ago, as of course did Katrina last month, so that's at least 25 Cat 5 hurricanes in the Atlantic including Rita.
Also of note is that Cat 5 Typhoons are quite normal in the Western Pacific; they had 11 Cat 5s in one year, 1997.
And so did Ivan last year...and Emily this year was right there, and may have briefly been a CAT 5