# GBI 2019, Blockchain Index, a Brand New Start.

Article Outline

Happy New Year!

This is the first post of the GBI.news team and we are happy to announce that the GBI.news (gbi.news) will usher in the biggest update.

The GBI index has been in running for two years, from 1000 points on January 1, 2017 to a maximum of 22,480 points. Now, it arounds 4,400 points, which means the trend of the blockchain asset market in the past two years.

After 2 years of running, we decide to do the last update. We will hand over the varieties and weights of the index into the market, and no longer have manual intervention.

The main updates are as follows:

1. The top 10 coins in the market value automatically become index components, which are corrected every 24 hours.
2. The trading volume of the top 10 trading platforms of the component varieties is the weighting ratio of the calculated components.

At present, GBI uses data with a market value of Coinmarketcap, and will build a new data source with the goal of being more accurate, fair and effective in the future.

## RULES

The final version of the index are weighted and calculated according to the market value.

Therefore, there are two core choices in the structure of the index: One is which varieties to choose; the other is the price of which exchanges to choose.

In principle, we should choose the most marketable coins, the top N coins with the highest market value.

The weight of the former N market value coins in the index depends on the proportion of the transaction volume of the varieties. The volume of trading is determined by selecting the larger top M exchanges from the global markets.

We calculate GBI as follows:

1. From the market, find the Top N coins in market value , the market value is
A_{i} (i < N)
1. From the market, find the Top M exchange in Top N coins, the volumes of which are:
V_{i,j}  (i < N, j < M)
1. Calculate the weight of each coins. The weight of the top 10 market value varieties in the index depends on the trading volume of the varieties.

Use V_{n} to indicate the trading volume of the top N coins in the past 24 hours (V means Volume), and the trading volume selects the sum of the trading volumes of the top ten exchanges in which the coins is located.

1. in which,
V\_{n} = \sum_{j=1}^{M}{V_{n,j}}
1. Therefore, we calculate the weight for the nth coins is:
   W\_{n} = \frac{V_{n}}{\sum_{i=1}^{N}{V_{i}}}
1. Finally, we calculate GBI for:
GBI = \frac{\sum_{i=1}^{N}{A_{i} \times W_{i}}}{A_{0}} \times \alpha \times 1000, (N=10)

in which,

α is used to ensure the continuity of the index when the calculation weight is updated.

## Manipulation prevention

The objectivity of the index is the essential of GBI, but it is also necessary to prevent the index from being manipulated.

We will continuously observe the market factors that constitute the index according to the principle of index calculation, and have destructive factors that constitute the objectivity of the index. All manual intervention rules are pre-established and ensure fairness and openness in the operation of the tool.

The intervention tools include：

• Exchange Watching Pool: Flow calculations are performed in the exchange's observation pool, and exchanges that meet the calculation requirements will participate in the index calculation.
• Pre-observation period: The new exchanges requires a 3-month pre-observation period before entering the observation pool.
• Trading volume cleaning: Trading volume generated by abnormal trading such as mining trading, bots and no-fee transactions will not be used.
• Terminate observation: If the exchange is found to have serious human factors affecting market behavior, the exchange will be removed from the observation pool.

GBI.news will become a more realistic indicator of market trends without the need for manual correction of components every year.

In 2019, in addition to the blockchain industry index, more functions will be opened.