A weakening global economy is pulling down the prices of energy and farm commodities.

The World Bank says that energy prices will drop 14.6% this year and 3.1% in 2020 and that farm prices will fall 4.7% this year and eke out 0.6% growth next year. The forecasts are sharply lower than what the anti-poverty agency was predicting in April.

Metals and minerals prices are expected to skid 5.2% this year and 1.4% in 2020.

The global economy has been decelerating, weighed down by trade tensions and a slowdown in China, the world's second-biggest economy.

The International Monetary Fund expects the world economy to grow just 3% this year, down from 3.6% in 2018, and world trade to expand 1.1%. Both are the weakest numbers since the recession year 2009.