
You can find more details how this seasonal patterns affect the exchange rate and more importantly how to correctly use them in your trading activity in one of my articles here: Seasonal Cycles in FX Trading
This seasonality cycles will only give you the tendency of an particular currency pair to bottom or top or rally or fall, at certain point in time. Going forward we're going to analyse what are the December seasonal patterns in FX market.
- EURO December Seasonal Patterns

Even thought both the 15yr and 10yr averages price, points to a strong euro in December the 5yr average price, which takes in account just the most recent action, points to a much more moderated gains. Taking in consideration that we're in a strong bearish trend and with the broad based dollar strength coupled with the dry in liquidity due to the holiday season we should expect much more narrow ranges.
- GBP December Seasonal Patterns

All the averages prices are basically saying the same thing narrow activity in the month of December as due to low liquidity and low volatility trading chase away during the holiday season so it's best to trade it from the short term perspective.
- AUD December Seasonal Pattern

- JPY December Seasonal Pattern

Best Regards,
Daytrader21