The Tokyo MoU reported that ship detentions in the Asia Pacific region were at their lowest in decades. But bad ships are getting even worse as the number of detainable deficiencies per ship increase.

In its annual report, Tokyo MoU, which surveys port state control information in multiple Asia-Pacific countries, reported 941 detentions in 2017.

"This is the lowest number and the first time less than 1,000 during the past two decades," the group said.