NEW YORK ( ETF Expert) -- According to the U.S. National Bureau of Economic Research, the "Great Recession" began in December 2007 and ended in June 2009.Eighteen months hardly constitutes a lengthy economic contraction. Just ask Portuguese and Spanish citizens whose countries have never quite recovered from the slump that began in the U.S. and spread across the globe. In fact, over the last five years, many might say that they've experienced a modern-day depression. Perhaps, then, the severity of the 2007-2009 downturn is the rationale for the term's enduring description. Or maybe the sub-par economic growth that has occurred since 2009 provides us with enough of a reason to question the turnaround's durability. Either way, the ghosts of the Great Recession haven't departed from our collective psyche. Need proof of the Great Recession's endurance? Simply ask yourself if Americans would be as eager to buy homes or cars were it not for the Federal Reserve's manipulation of interest rates. Indeed, the Fed's zero-interest-rate policy combined with its unconventional quantitative easing explains why our gross domestic product has averaged 2% annually over the last 3 years. (Strangely enough, it may also be a contributing factor behind why America is not able to grow at 3% annually.) One might think that if the Great Recession ended four years ago, the U.S. central bank would be able to end its policy of electronically creating dollars and subsequently buying U.S. Treasury bonds. Yet, the mere mention of the Fed "tapering" bond purchases caused a ripple effect across most assets along the risk spectrum. Hardest hit? Exchange-traded funds with conspicuous yields -- funds dedicated to real estate investment trusts, high yield corporate bonds and emerging market debt. Even one of the more durable asset classes of the last few years (i.e., U.S. common stocks) was subject to capital depreciation and volatile price swings. Lately, popular U.S. stock ETFs have been running into technical resistance in their attempt to reclaim all-time highs. Trendlines that once served as support for those ETFs are currently acting as impediments. For example, the SPDR S&P 500 Trust ( SPY) used to bounce higher off of its 50-day moving average; today, the same trendline is more like the Great Barrier Reef.