If you are wondering which currency, other than the U.S. dollar, to hold at the start of a new year, past trades show you'll be better off with euros. Using data analytics platform Kensho, CNBC looked at the average return when holding sterling, euros and the yen against the dollar at the start of a new year. It concluded that for the last three years, you'd have been mostly better off with euros. "Last year, most people went into the year with the view that the USD (dollar) was going to continue to rally strongly due largely to the expected stimulus from President Trump's policies," Itay Tuchman, global head of foreign exchange trade at Citi, told CNBC via email. "Add to this mix that both the EUR (euro) and the GBP (sterling) were facing significant uncertainties from a political perspective, which would keep them under pressure," he added.

Looking at the last week of trading of 2016 and the first week of 2017, the euro gave a 0.73 percent average return against the dollar. By contrast, both sterling and the yen produced negative returns. Going into 2017, Europe was mostly overshadowed by political uncertainty with three key elections on the horizon. However, its growth story offset some of the political concerns. The region has finally returned to growth after years of economic crisis. On the other hand, the U.K. was embroiled in economic uncertainty following its decision to leave the European Union and Japan had seen sluggish growth going into 2017, with its central banks cutting rates, and thus depreciating the yen.

A year earlier, the dawn of 2016 showed a similar picture. Though all of the currencies in analysis produced negative returns, this wasn't so profound for the euro. However, as the world entered 2015, the return on the euro against the dollar was negative by 2.55 percent, mostly due to the deep economic crisis that Europe was facing.

"Straight from the 'off' this year, German economic data was surprising on the upside. The result was that the market immediately started to re-evaluate its outlook for the EUR," Jane Foley, head of forex strategy at Rabobank, told CNBC via email. However, she added that the strength seen in the euro at the start of 2017, was not "typical" of recent years. "Of the G10 currencies only the JPY (yen) consistently makes it in the top three performers over the last three years when looking at dates between approximately December 20 to January 1. This is suggestive of some increase in geopolitical tension towards the holiday period," she said. "That said, before we all start buying the JPY we should consider that strong levels of world economic growth currently could counter an appreciation in the JPY at the end of this year."

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