Concern continues to grow over the outlook for inflation in the euro zone, reflected in regular efforts by the European Central Bank over the past month to rein in any further gains for the euro.
Another low figure would add to pressure for the bank to take more steps to flush extra euros through the banking system and into the real economy.
"After the German numbers yesterday, it certainly looks like we may get an undershoot in euro-area inflation," said Paul Robson, strategist with RBS in London. "To some extent that is in the price, but I think it will keep the euro on the back foot if we get a weaker number."
The euro was less than 0.1 percent lower on the day at $1.3806 having retreated from Tuesday's intraday high of $1.3880. The yen gained just under 0.2 percent against both the dollar and the euro, to 102.49 and 141.49 yen respectively.
Despite all the bearish signals for the euro, it remains within shouting distance of levels above $1.39 reached last month, its highest since late 2011. Broadly, that seems to be the result of Germany's large current account surplus and inflows of portfolio capital to European bond and stock markets.
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"Every trader I know in London seems to be calling for a weaker euro. You can't find anyone who wants it higher, yet it does not want to fall," said a dealer with one London bank. "At that point you just find yourself trading off a square book and waiting for a clearer trend to re-emerge."
The yuan's losses this year, its first major turnaround in more than a decade, are seen by many as having important ramifications for the major developed-world currencies.