BingX will **continuously introduce data from multiple trading platforms into the "Latest Index" of Perpetual Swap** to improve the stability of the latest index price as well as to reduce index price deviations.

Currently, the latest Price Index for Perpetual Swap derives prices from Binance, Huobi, OKEx, Coinbase, Bitstamp, Bittrex, Gate, MXC & Kraken.

**Notes:**

- If there are multiple pairs of the same underlying asset on the same exchange, only one of them will be adopted, with priority given to the USDT-margined pair, and if there is no USDT-margined pair, the USDC- or USD-margined pair will be adopted.
- The price calculation weights of each external exchange are the same.
- BingX will adopt data of the external exchanges that are in line with the current system time. If the data of an external exchange is returned more than 5s earlier/later than the current system time, the exchange will be ignored in this calculation.
- Each time the price index is updated, the Mark Price is also updated.
- When the deviation between the last price of an external exchange and the median of all the above exchanges’ price is ≥ 3%, that external exchange will not be included in the Price Index Calculation for the next 5 minutes. | After 5 minutes the system will check the price of that exchange again and if the price deviation returns to the normal level, that exchange will be re-included to the price index calculation, and if not, it will not be included. | In case of non-inclusion in the calculation of the price index for 4 consecutive times within 30 minutes, it is considered that the price deviation of that exchange is too large and the system will no longer evaluate the conditions for restoration; instead, a manual review is required to determine whether the exchange will be included in the calculation of the price index or not.

**Mark Price Calculation** ( of Perpetual Swap only)**:**

Mark Price = Median * ( Price 1, Price 2, Perpetual Swap Latest Price)

Price 1 = Price Index * { 1 + Last Funding Rate * [ Time Until Funding (hour) /8]}

Price 2 = Price Index + Moving Average (30-minute Basis) [ ( Bid1 + Ask1) / 2- Price Index]

- For Moving Average (30-minute Basis), the measure takes place every minute in a 30-minute interval.
- Let x = ( Bid1 + Ask1) / 2 - Price Index, then Moving Average (30-minute Basis) = SUM ( X1~X30) / 30.

**Example:**

Take the index price of BTC/USDT as an example to calculate.

Assume the latest BTC prices of Binance, Huobi, OKEx, Coinbase, Bitstamp, Bittrex, Gate, MXC, and Kraken are P1~P9 respectively.

- P1~P9, sorted by smallest to largest to take the median. Name Pmedian, assuming Pmedian=P5
- Calculate |Px/Pmedian-1|, if the result is greater than 3%, then eliminate Px
- The retained Px are reassigned equal weights, assuming that the final retention is (P1, P3 ~ P8), a total of seven, then Weight = 1/7
- Index Price "PIndex" = P1 * Weight + P3 * Weight + ... + P8 * Weight

So, the index price of BTC/USDT is PIndex.

BingX reserves the right in its sole discretion to amend or change or cancel this announcement at any time and for any reasons without prior notice.

**Risk Warning:**

Trading digital assets and their derivatives is highly leveraged and risky and may result in partial or total loss of account funds. Before conducting spot/contract trading, investors must ensure that they understand the nature and rules of spot/contract trading, and decide whether to participate in spot/contract trading based on their investment experience, goals, financial status, and ability to bear risks.

BingX Operation Team

12/16/2021