All data is fetched directly from exchanges through their APIs. I always try to make sure that the data is accurate and I'm in contact with exchanges in case something is not right.
Can we use it?
Sure. Please provide the data source. Best way to get the raw data is to visit
data.bitcoinity.org
and under the chart you have CSV and XLSX export funcitons. If you need some other format or some data that you can't find on the website, let me know.
Who is running this site?
Me, Kacper Cieśla. One man operation. While I do insert some random gifs on the website and don't try to make it look very serious, I do take accuracy of presented data very seriously.
Random notes
Volume is not the best way to measure which exchange is the biggest or in which currency there is most activity, it may vary widely e.g. depending on whether any trading fees are present. It's also not something that can be verified in any way. If exchange says it traded that many bitcoins, that's what gets displayed. Consider using
rank
or some other indicators that you can find e.g. on the
exchanges list
If you present some chart of e.g. comparison of different currencies, please note that when I add some new exchange, I also import their historical data, so the distribution between currencies may change. I try to cover the most important parts of the market so the change shouldn't be big, but importing historical data from new exchanges is something that can change the look of some past charts.
There really is no public data available on how much trading is happening in specific countries. The only separation is by currencies. Traders are free to trade in any currencies available regardless of their country of residence.