And it was in 2010, 2011, 2012, 2013.
Top 5 strongest currencies in 2015
(Change against US $ at 12 December 2015 against rates one year ago)
Bitcoin (XBT) +21%
Israeli Shekel (ILS) +2%
US Dollar (USD)
Swiss Franc (CHF) -2%
Japanese Yen (JPY) - 2%
Bottom 5 weakest currencies in 2015
Venezuelan Bolivar (Black market rate) -78%
Ukrainian Hryvnia (UAH) -34%
Brazilian Real (BRL) -33%
South African Rand (ZAR) -31%
Colombian Peso (COP) -28%
Big Mac Index % over-undervaluation Vs.$
SG Kinsman
https://medium.com/@BambouClub/best-and-worst-performing-currencies-in-2015-d1e62088bc29#.oj7qz6ymtI am a big follower of bitcoin. I like it very much and I have hoped on it. I have three years in which I invest continuously on it (buying, investing, earning from some investments and losing from some others). So for me to see the data given at main post (for more not given or created by his desire but based at one source) are joy and hope. But my data tell that the data given from OP at his main post could not be correct. Or better. The data given by its source seems doubt for me. Regarding the data given for us dollar. I would give only two facts. The first is seen and proven by me myself. In my country the value of us dollar was increased more that 25% during the previous year and the currency of my country was not devalued during all the 2015. Then I found this source at internet (which to tell the true is made in early 2015 news - that mean that after can have been happen other things - and that speak about a totally different behavior of it). So what to believe: my eyes and this source or the source of OP? I believe more to my eyes. The source (from CNN - much more reputable than the source of OP):
http://money.cnn.com/2015/03/16/investing/us-dollar-fastest-rise-40-years/