Attacks against merchant ships off the coast of Somalia fell to a six-year low  in the third quarter of the year with the increase of armed guards on vessels and naval patrols, the London-based International Maritime Bureau reported. There was one attack on a ship, compared to 36 in the same time period last year.

There was a total of $1.3 billion spent by various governments on military interventions, including naval patrols, in the region aimed at preventing attacks. Maritime piracy attacks are estimated to have cost the maritime industry and governments $6.9 billion last year alone.

“We welcome the successful robust targeting of pirate action groups by international navies in the high-risk waters off Somalia,” IMB Director Pottengal Mukundan said in the report. “There can be no room for complacency. These waters are still extremely high-risk and the naval presence must be maintained.”

The IMB has tracked pirate activity since 1991.