Based on the aggregated intelligence of 180,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, the iShares Barclays 20+ Year Treasury Bond Fund (NYSE: TLT) has received the dreaded one-star ranking.

With that in mind, let's take a closer look at TLT and see what CAPS investors are saying about the ETF right now.

TLT facts

Inception July 2002
Total Net Assets $3.5 billion
Investment Approach Seeks to approximate the total rate of return of the long-term sector of the United States Treasury market as defined by the Barclays U.S. 20+ Year Treasury Bond Index.
Expense Ratio 0.15%
1-Year / 3-Year / 5-Year Annualized Returns 21% / 13.5% / 11.6%
Alternatives SPDR Barclays Capital Long Term Treasury
Vanguard Extended Duration Treasury Index ETF
iShares Lehman Aggregate Bond

Sources: S&P Capital IQ and Motley Fool CAPS.

On CAPS, 93% of the 184 All-Star members who have rated the iShares fund believe the ETF will underperform the S&P 500 going forward.

Earlier this month, one of those Fools, fellow colleague John Divine (TMFDivine), succinctly summed up the bear case for our community: 

Insanely low rates must return to levels a little closer to normal. Some sort of deviation to the mean will happen within the next 5 years, and when that happens, TLT will suffer vs. the S&P. Underperform.

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Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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