A total of 297 ships were attacked in 2012, compared with 439 in 2011.
A big drop in Somali piracy brought the figure down, the IMB said, with 75 vessels reporting attacks, compared to 237 the year before.
West and East Africa remained the most dangerous areas worldwide, with 150 attacks last year.
Gunmen managed to board 174 vessels globally, with 28 of those being hijacked and 28 fired on.
There
