The vast majority of bitcoin trading quantity has traditionally been dealt with by a relatively small number of trades.
However, the latest data indicates that quantity has concentrated even further because smaller exchanges are being forced aside, leaving them with a much lower share of the complete volume of bitcoins traded than just a few months ago.
Prior to the start of its decrease in mid-2013, Mt. Gox had what amounted to an effective monopoly on bitcoin trading volume, often ordering upwards of 80-90% of complete US dollar-denominated volume.
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