In the United States alone, an unprecedented 77 million baby-boomers will be living the next 20 to 30 years in retirement. With long lives ahead of them — and without adequate planning — what are the risks they are facing? According to Olivia Mitchell , Wharton professor of insurance and risk management, and Christopher “Kip” Condron, president and CEO of AXA Financial, the world’s largest financial services firm, the rising tide of boomers in the U.S. and around the world needs to meet challenges that previous generations never faced, including changes to key retirement institutions, as well as medical-care cost inflation and the “lump-sum illusion” — the tendency to view retirement savings as a lump sum, as opposed to a prospective income stream. Knowledge at Wharton spoke with Mitchell and Condron about how the financial services industry is working to meet the needs of this next wave of retirees.…