The dollar has been on an absolute tear recently. And in the last four years, it's appreciated by 25% on a trade-weighted basis (compared to the countries the US trades with). Almost every country in the world has contributed to that, except one: China.
Here's how that looks, with a chart from Deutsche Bank analysts on Friday:
Deutsche Bank
The Chinese renminbi is pretty much the only major economy with a currency that has appreciated against the dollar over this period. More recently it's declined against the dollar, but over the past 10 years the Chinese currency has appreciated considerably.
In fact, here's how the dollar to renminbi exchange rate has slumped during that period:
Google Finance