The problem of validating trading volume
In the past, there have been reports that Chinese exchanges have fabricated trading volume figures. These reports have included OKCoin, which is featured in the CoinDesk market share figures above.
The reason why an exchange might want to fabricate trading data is quite simple: the more volume an exchange appears to have, the more likely it is that liquidity-seeking traders will be attracted to that particular exchange.
What makes inflating volume data even more tempting is that, unlike bitcoin price data, there is no outside independent method available to easily verify exchange reported volume data.
It was for this reason that CoinDesk has been reluctant to launch a CNY index in the past.
Trading volume at BTC China and OKCoin
As the bitcoin exchange market matures, one can imagine a day when independent auditors will verify reported volume data, similar to how professional accounting firms certify the public financial statements for corporations.
In the meantime, the closest approximation we have to independent auditors are venture capital firms, which are investing in various bitcoin exchanges.
Recently, OKCoin reportedly received a major investment of $10m from several VC firms. Prior to this BTC China also received a $5m investment from a reputable firm (Lightspeed).
The closest approximation we have to independent audits are the venture capital firms investing funds in various bitcoin exchanges. We can reasonably expect that, given how important volume data is to the value of an exchange investment, that these venture firms audited both BTC China's and OKCoin’s internal volume records as part of their due diligence process.
There is another recent development which provides a greater degree of comfort with OKCoin's volume figures, which is BTC China’s announcement that it would be following OKCoin’s approach of charging zero commission on trading. CoinDesk views this shift in BTC China’s strategy as evidence that OKCoin’s zero commission approach is having a competitive impact on BTC China’s business.
For these reasons the CNY index will initially include BTC China and OKCoin.
What about Huobi?
There is another Chinese exchange which reports significant volume which is roughly on par with OKCoin, and that is Huobi.
Like OKCoin, there have been reports that Huobi has fabricated trading data. However, Huobi has not to our knowledge received a large investment from a reputable venture firm. Hence, for the time being we are not including Huobi in the new CNY index.
If we were to include Huobi in the earlier total market share calculation we can see how Huobi would substantially increase the total CNY share of trading from 70% to 81% (Charts 4 and 5).