Here’s a shocking consequence of our love for plastic, according to a new report (PDF) from the World Economic Forum: We’re putting so much of the cheap, non-biodegradable packaging material into the ocean that by 2050, ocean plastic will literally outweigh ocean fish.

“This report demonstrates the importance of triggering a revolution in the plastics industrial ecosystem and is a first step to showing how to transform the way plastics move through our economy,” said WEF’s Dominic Waughray when the report was unveiled at Davos this week.

The amount of plastic in the ocean today is estimated at 150 million metric tons (tonnes). Worldwide plastic production is expected to double within the next 20 years—having already multiplied by 20 since 1964.

The proportion of plastic deposited in the ocean is expected to increase at a rate of 4.8% each year until 2025, according to the report, and at a rate of 3% from 2025 to 2050.

This analysis operates on the assumption that the total mass of all the fish in the sea is around 1,000 million tonnes, and that this number won’t significantly increase or decrease in the coming decades. In that case, by 2025, when the ocean contains a projected 250 million tonnes of plastic, the ratio of plastic to fish will be roughly one to three. In 2050, if the pattern continues, the ratio will be one to one—with a slight edge for the plastic.