It makes the trading price near the spot index price. If the funding rate is positive, long positions will receive the funding; if the funding rate is negative, shorts will receive it. The funding will be paid/received every 8 hours, and it only takes place in the following timestamps: 20:00, 04:00, and 12:00 (UTC).
Funding = Position Value * Funding Rate
Funding Rate (F) = Premium Index (P) + clamp (Interest Rate (I) - Premium Index (P), 0.05%, -0.05%)
|1. If (I - P) is within +/- 0.05%, then F = P + (I-P) = I. In other words, the Funding Rate will be equal to the Interest Rate.
2. If (I - P) is less than -0.05%, then F = P -0.05%,
3. If (I - P) is greater than 0.05%, then F = P + 0.05%.
In the Funding Rate Calculation：
The Interest Rate = 0
Premium Index (P) = (Max (0, Impact Bid Price - Mark Price) - Max (0, Mark Price - Impact Mark Price)) / Spot Price + Current Funding Rate
Impact Bid Price = the average price of "Impact Margin Amount" for bidders
Impact Mark Price = the average price of the "Impact Margin Amount" for sellers
"Impact Margin Notional" refers to the total amount of the order book, e.g. BTCUSD is 10 BTC.
a. The initial Funding Rate is 0. The Funding Rate is used to calculate the current Premium, and the current premium is used to calculate the next Funding Rate.
b. CoinEx calculates the Premium Index (P) every minute, and then performs an 8-hour Time-Weighted-Average-Price (TWAP) over the series of minute rates.
c. Limit of the Funding Rate:
The maximum absolute value of the Funding Rate = 0.375%