Goldman Sachs' projection of the 20 largest economies in 2050. GDPs in trillions (US) 1. China $70.710 2. USA $38.514 3. India $37.688 4. Brazil $11.366 5. Mexico $9.340 6. Russia $8.580 7. Indonesia $7.010 8. Japan $6.677 9. UK $5.133 10. Germany $5.024 11. Nigeria $4.640 12. France $4.592 13. Sou...