On September 29th, 2022 at 12:00 UTC, the timescale of the funding rate for all perpetual contracts changed from a 4 hour window for calculation and settlement to a 1 hour window for calculation and settlement. The maximum permissible rate also increased, from 0.1% to 0.25%.
The following support articles have been updated with the details of the new funding rate methodology:
This page exists to document the prior method for funding rate calculation and examples, which can be found below.
Pre-September 2022 Funding Rate Methodology
|Auto-Roll Period||Every 4-Hours on 12 UTC, 16 UTC, 20 UTC, 24 UTC, 4 UTC, 8 UTC|
|Rate-setting Calculation Window||Rate for next period is calculated over current 4-hour period (e.g., rate for 12-16 UTC period is calculated in window between 8-12 UTC)|
Between start and end of Rate-setting Period the Funding Rate is computed as the time-weighted average premium, and standardised to a per-hour basis.
Permissible range per 1 hours: [-0.1%, +0.1%] (i.e., 80 basis point magnitude for 8-hour realisation period)
Continuously based on Funding Rate set at the end of the prior Funding Period.
Positions will immediately and continuously receive or send funding while open in the perpetual contracts.
The funding accumulates as UPL and settles every four hours at end of Funding Period, or when user changes net open position (whichever occurs first).
|Funding Rate Multiplier||
n = 8
This is the coefficient used in the calculation of the funding rate.
A value of 1/n means that, ceteris paribus, it will take n hours to realise the Average Premium.
Example: if the Average Premium is 0.32% for the 4-hour period, then Funding Rate is equal to 0.04%, meaning that over the course of 8 hours, this 0.32% total will be realised.
|Funding Rate Calculation||
In a given 4-hour Funding Period, Premium values calculated from minutely perpetual contract prices (240 observations) using an Impact Mid are recorded versus the Real Time Platform Ticker.
The Impact Mid is the median of the average entry price market-selling x value of contracts and market-buying x value of contracts. See table above for contract-specific values.
The Average Premium is calculated as the average of the mid 120 values recorded from the above 240 observations.
Finally, this value is weighted by the Funding Rate Multiplier.
If Average Premium is greater than 0 for the 4 hour period, those in Long positions will continuously pay out to Short positions, which pushes the price closer to Index.
If Average Premium is less than 0 for the 4 hour period, those in Short positions will continuously pay out to Long positions, which pushes the price closer to Index.
In order to get a complete understanding of the funding rate dynamics of the Inverse Perpetual Contract, we present examples to demonstrate the key features.
Example Funding Rate 1: (8-hour rate realisation length)
Assume time is 12 UTC and that price of BTC is $7,000 (via realtime index) and the Perpetual trades at $7,010 the whole time until 16 UTC. The average premium is computed as 0.1428% for the 4-hour period ($10/$7,000). This leads to a funding rate of 0.1428 / 8 = 0.01785% per hour.
Now assume that you are in a short position of 100,000 Contracts. If you hold this position from 16 to 24 UTC and the premium in 16-20 UTC period remains as 0.1428%, then you will earn interest of $142 for the eight-hour period ($100,000*0.001428) in BTC terms, so $142/$7,000 = 0.0204 BTC.
Example Funding Rate 2: (Maximum rate)
Assume time is 12 UTC and that price of BTC is $7,000 and the Perpetual trades at $7,100 until 16 UTC. The average premium is computed as 1.428% for the 4-hour period. This leads to a funding rate of 1.428 / 8 = 0.1785% per hour.
The maximum funding rate per hour in any given period is 0.1%. The minimum is -0.1%.
As a result. this 0.1785% hourly rate is floored to 0.1% per hour, so that the maximum 8-hour realisation will not exceed 0.80%.
Note that there is no "dampening" of rates done in this model: if a four-hour computed rate is near 0, then it will stay pay out non-0 value even if it is de minimis.
Example Funding Rate 3: (Absolute vs. relative rate)
Assume time is 12 UTC and that the real-time index price of BTCUSD is $7,000 and the relative rate set for the four-hour period is 0.05% per hour.
Now assume the time is 14 UTC and the Perpetual trades at $8,000 and you enter a Short position of 125,000 contracts at this price.
You will immediately begin receiving funding at an absolute rate of 0.05%/$7,000 = 0.000007142% per hour per contract unit.
In your account log you will then see this rate applying in your unrealised PnL through continuous funding payout equal to:
- 0.00000007142 * 125,000 = 0.008928 BTC per hour
- 0.00000248 BTC per second
This will pay out continuously until 16 UTC where the relative funding rate will change based on the market activity between 12-16 UTC.
Assume this new relative funding rate is now 0.03% and the real-time spot index is $7,900 for BTCUSD at 16 UTC.
In your 125,000 Contract short position at the end of the 2 hour period you will have 0.017856 BTC applied in your account log at 16 UTC.
From 16 UTC to 20 UTC a new absolute funding rate will begin applying of 0.03%/$7,900=0.000003797% per hour per contract unit.
Example Funding Rate 4: (Variable inter-period rate)
Assume time is 14 UTC and you enter a position long 200,000 Contracts on BTCUSD at $7,000. Assume that the funding rate for the four-hour period (12-16 UTC) is set as -0.04% per hour.
At 16 UTC, after you have held this position for two full hours, you will have earned $80 per hour (0.0004*$200,000). This is $80*2=$160 USD equivalent or $160/$7,000 = 0.0228 BTC, which credits continuously throughout the two hour period you hold it.
However, during this period , the price was at a premium and so the new four-hour rate set for 16 - 20 UTC is 0.04% per hour. After two hours of holding the position, you have paid 0.0228 BTC and you close at 18 UTC, two hours later.
Your funding for the four hour period you held the position is thus 0.0228 BTC for the last two hours of first period then -0.0228 BTC for the first two hours of the second period and your net flows are 0 for this.
Example Funding Rate 5: (Fixed intra-period rate)
Assume time is 14 UTC and you enter a position long 500,000 Contracts on BTCUSD with realtime index at $7,000. Assume that the funding rate for the four-hour period (12-16 UTC) is set as 0.033% per hour.
At 16 UTC, after you have held this position for two full hours, you will have paid $165 per hour (500,000*0.00033). For two hours this costs $165*2=$330 USD equivalent or $330/$7,000 = 0.04714 BTC, which debits from your position continuously throughout the two hour period you hold it, in the form of Unrealised Profit/Loss (UPL).
Example Funding Rate 6: (Booking of unrealised funding)
Assume it's 12 UTC you are in a 250,000 Contract long position on BTCUSD with realtime index at $7,000 and the rate in the funding period is -0.05%. This earns you funding of:
- 0.0005 * 250,000 = $125
- $125/$7,000=0.01785 BTC per hour
- 0.0002976 BTC per minute
- 0.00000496 BTC per second
- 0.00000000496 BTC per millisecond
This credits and debits every millisecond to every user with an open position. It credits first as "UPL" which is "unrealised" profit and loss, but you have the funds available right away to use in further positions or transfer into your Cash account.
The funding accumulates as UPL and is booked into your account log and realised when one of the following events occur:
1. You adjust your open position up or down by any amount
2. You hold until the end of the Funding Period, at which point it is booked (occurs every four hours)