'It gets worse before it gets better' - Swenson

STORY: "I think it gets worse before it gets better," he said, adding, "I think at this point there's probably not a lot that they can do or say to make the market feel any better."

The S&P 500 and the Nasdaq logged their worst weekly percentage drop since June on Friday, dropping as investors priced in the prospect of the Fed raising rates at least 75 basis points at the end of Wednesday's meeting.

Worries of Fed tightening have led to a 19% decline in the S&P 500 this year, with a recent dire earnings report from delivery firm FedEx Corp, an inverted U.S. Treasury yield curve and warnings from the World Bank and the IMF about an impending global economic slowdown adding to the woes.