The 1967 "summer of love" may have initiated a major political and cultural shift, but 2013 looks set to produce a sizeable change in the blood pressure of investors, with a "summer of volatility" keeping traders fixed to their screens.
Emerging market currencies have plunged, safe-haven bond yields are creeping higher, high-yielding debt has shown signs of crumbling. Equities are near all-time highs and the Nikkei, which at its 2013 peak was 46 percent higher year-to-date, has now tanked 16 percent in 10 days.
A stronger yen, stalling growth in China and the failure of Japan's Prime Minister Shinzo Abe to alleviate concerns may have played their part, but investors still only have eyes for the U.S. Federal Reserve.
"We will see Fed 'taper fear' ebb and flow all summer," Kit Juckes, global head of FX strategy at Societe Generale said in a morning note.
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"The Taper-debate rumbles but it's a question of when, not if policy gets less easy. That's probably the lesson from recent 'mixed' data; I meet plenty of people who think any talk of U.S. rate normalization is premature, but nearly all concede 'new normal neutral' is much higher than here."
The match was lit May 22 when yields on 10-year benchmark U.S. Treasurys rose above 2 percent after the Federal Reserve's latest policy minutes were released. Investors reacted to the central bank's comments that it could start tapering off its bond purchasing program – a scheme which has fueled the recent bull run - as soon as this month.
(Read More: Why the Emerging Market Bull Run Is Over)