Expansionary monetary policy impact euro quite significantly

The exchange rate channel is probably the fastest to bear fruit as the depreciation of the euro started well before QE was actually announced. The euro, both versus the dollar and on a trade-weighted basis, peaked when President Draghi announced upcoming unconventional measures at the May 2014 ECB meeting. 

A lower euro is expected to raise the level of inflation with a lag, as higher import prices gradually feed into consumer prices, and boost economic activity through higher export competitiveness. 

"Beyond a 5% depreciation for the TWI and a 10% depreciation for the bilateral exchange rate, the impact on growth and inflation should eventually be meaningful and between 0 and these thresholds, the impact is only small. An appreciation of the euro would have the opposite effect", says Barclays.