Number of spills
Over 1800 spills have been recorded since 1970. The yearly average recorded for both medium (7–700 tonnes) and large spills (>700 tonnes) this decade is less than a tenth of the average recorded in the 1970s.
The lowest annual number of spills was recorded in 2019 and the highest in 1974.
Quantities of oil spilt
Approximately 5.86 million tonnes of oil have been lost as a result of tanker incidents globally since 1970. However, there has been a significant reduction in volume of oil spilt through the decades. The total amount spilt per decade has reduced by about 95% since the 1970s.
A few large spills are responsible for most of the oil spilt annually or in a decade.
An interesting pattern of alternating sharp decline and stability can be observed for average volume of oil spilt per decade. Nonetheless, quantity of oil spilt in a particular year or a decade is unpredictable, and trend can be hugely distorted by a single large spill.