The Organisation for Economic Co-operation and Development (OECD) says that every economy it monitors suffered a slowdown during September.
The OECD's leading indicators index for the month is designed to highlight turning points in economic activity.
The data showed growth slowing in all OECD countries and major developing economies monitored by the group.
The OECD represents developed economies including the US, UK and Japan.
The index tracks economic growth relative to the long-term trend for individual economies.
Japan, Russia and the US saw their economies reverting to trend.
However, Canada, France, Germany, Italy, the UK, Brazil, China, India and the euro area appeared to be falling below their long-term trend.
In September, the OECD said it expected GDP to slow around the world.
The OECD expects 0.3% growth in the UK in the last three months of the year, but said the economy could contract by as much as 1%, amid high uncertainty over its projections.
It predicted the Group of Seven largest economies would grow by just 0.2%, while Germany could be most affected by a downturn in global trade.
It estimated the German economy would contract by 1.4% in the last quarter of 2011.