Currently the 28 EU member states make up a little over 22 percent of world gross domestic product (GDP). This is down on the over 36 percent the same nations possessed in 1960.
However according to a new survey this will fall further, to just 9.9 percent in 2100.
The real figure is likely to be even lower as the study doesn’t incorporate the UK upcoming withdrawal from the EU.
Britain is set to leave the EU on January 31, with Boris Johnson having secured a Parliamentary majority for this objective.
The study was conducted by the University of Denver’s Pardee Centre.
In addition Britain is projected to be the only current EU member state that improves its place in the ranking of the worlds largest economies by 2100.
Next year the UK will have the world’s seventh biggest economy according to the study.
However the country is predicted to rise to sixth place by 2100.
All other current EU member states will see their relative position decline during this period.
READ MORE: EU could demand Brexit extension to keep Britain tied down till 2020
Croatia, Lithuania and Bulgaria are projected to lose half their populations by 2100.
Only eight current EU member states, including the UK, are expected to see their populations increase.
Of the ten countries expected to see the biggest growth in GDP rankings only one, Tajikistan, is not in Africa.
Rwanda tops the list and is expected to see its position rise by 86 places.
In 2100 India is expected to have the worlds biggest economy, with 19.8 percent of global GDP, followed by China and the US.
Britain has set a hard deadline of December 2020 for reaching a new trade deal with the EU.
But the European Commission President said both sides needed to seriously think about whether this is enough time to negotiate a new trade deal and work out agreements about a series of other issues.
Ms Von der Leyen told French daily newspaper Les Echos: “It would be reasonable to evaluate the situation mid-year and then, if necessary, agree on extending the transition period.”
In separate comments to German magazine Der Spiegel, Ms Von der Leyen added the UK’s departure deadline on December 31 “worries her a lot.”
She said: “That worries me a lot, because time is extremely short for the mass of issues that have to be negotiated.”
She said earlier this month that this timeframe is “extremely short” to discuss not only trade issues but also education, transport, fisheries and other issues.