From mid-2012 until the beginning of 2014, US treasuries were in a steep decline (yield rising) in expectations of Fed rate hikes that never came. 

2014 was a great year for treasury bulls, undoing the carnage of the previous year and then some. 30-year treasuries hit a record low yield.

So far, 2015 has been a bad year for the bulls. 

Monthly Yield Curve 2005-2015

Charts courtesy of Curve Watchers Anonymous. 

Daily Yield Curve 2015

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