CoinDesk has created a new Bitcoin Price Index (BPI) based on the price and volume of bitcoins exchanged for Chinese yuan (CNY).

The new Chinese yuan BPI is separate from the existing and widely referenced CoinDesk USD index, which CoinDesk will continue to maintain.

The USD index and CNY index will complement each other by providing the most trusted bitcoin price in the two most commonly exchanged national currencies.

The rise of bitcoin in China was a one of the big stories and catalysts in the latter half of 2013.

Near the end of last year, CNY trading volume at Beijing-based BTC China surpassed the USD trading taking place at the leading exchanges of that time (by USD volume) – Mt. Gox and Bitstamp (see Chart 1).

However, following China's restrictions on bitcoin transactions with banks in December, bitcoin trading in China suffered a significant setback. Bitcoin trading in USD was once again seen as returning to dominance.

Today, many sites which track overall bitcoin trading volumes show total bitcoin volume in USD as leading CNY trading by a very wide margin.

For example, Chart 2 below from the widely-referenced site Bitcoincharts.com shows USD and CNY share of total bitcoin volume at 83% and 11%, respectively.

Another widely referenced site for bitcoin prices and volume, BitcoinAverage.com, also tells a very similar story (Table 1).

However, contrary to the figures shown on Bitcoincharts.com, BitcoinAverage.com, and other sties, CoinDesk believes that bitcoin trading in CNY may be underreported by a significant margin (Chart 3).

The above Chart 3 depicts the self-reported volume from five leading exchanges trading bitcoin in USD and CNY as shown below in Table 2.

The difference CoinDesk calculates for bitcoin trading market share – compared to what is shown on Bitcoincharts.com and BitcoinAverage.com – regards CNY trading, not USD trading.

The vast majority of USD bitcoin trading is taking place on just the top three exchanges: Bitstamp, BTC-e and Bitfinex. These three exchanges represent over 99%+ of total USD volume. CoinDesk’s USD figures more-or-less agree with BitcoinCharts.com and BitcoinAverage.com

Where CoinDesk respectfully disagrees with BitcoinCharts.com and BitcoinAverage.com (among other sites) is on completely excluding some Chinese CNY exchanges when calculating overall trading volume market share.

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.

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.

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).

In addition to the significant volume of bitcoins which are exchanged for CNY, events (or rumors) from China are once again having a material influence on bitcoin.

Overall, while there are reasons to be skeptical of self-reported bitcoin volumes, China is clearly a very important market for bitcoin, and CoinDesk feels it is important to launch a dedicated CNY Bitcoin Price Index.

The CNY index will be calculated in the same manner as the USD index, meaning it will be based on prices and volumes for bitcoins traded exclusively for CNY (just as the USD index is based solely on USD trades). In this way the two CoinDesk BPIs reflect a true bitcoin market price, not an artificial or blended price derived from another exchange rate.

Look for the CNY index in the upper right corner of the CoinDesk homepage and explore our BPI page for CNY index charts, alongside other analytical tools and raw data today.

Yuan Note Image via Shutterstock