Global stock markets signed off on their worst three months in four years on Wednesday.
Markets saw falls of between 7% and 15% over the three months with the Shanghai index falling furthest, down 25%.
Confidence in stocks has been hit by the crisis in Greece, the Chinese slowdown and the threat of higher interest rates.
However, most markets ended the month with a final flourish, some making gains for the single day of over 2%.
On Wednesday, the Dow Jones, the main American index, ended up about 1.5%. The London FTSE 100 bounced up 2.58%
But some economists believe the economy is strong enough to withstand a rate rise.
Peter Morici, business professor at the University of Maryland, said: "Overall, a Fed interest rate increase won't harm growth and jobs creation, and the Fed is likely to begin gradually raising rates at its October or December policymaking meetings.