Sub-zero interest rates could be problematic in U.S.: Fed's Bullard

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ISHARES 20+ YEAR TREASURY BOND ETF (NASDAQ: TLT) Delayed: 80.22 +0.09 (0.11%)
Previous Close $80.13    52 Week High $143.62 
Open $80.32    52 Week Low $118.66 
Day High $80.47    P/E N/A 
Day Low $80.08    EPS $0.00 
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