EUR-USD Rate Differential

 | Dec 30, 2014 11:12AM ET

There are many things behind the decline in the euro that pushed from $1.40 in early May to fresh two-year lows yesterday. Chief among those reasons, we posit, is the diverging trajectory of monetary policy.

The Great Graphic, created on Bloomberg, shows the euro-dollar exchange rate (yellow line) and the discount Germany pays under the US to borrow 2-year money (white line). Here is Q4 the two time series appear to be moving in lockstep again after diverging somewhat in Q3.