# Borrowing Fee

<figure><img src="https://content.gitbook.com/content/YQMiWMjQNj4QgmzaRycI/blobs/YiY3a2r8ZBJ0TJIbNBwx/12.png" alt=""><figcaption></figcaption></figure>

### Borrowing Fee Formula

VolFactor: VF (Involved ATR), Clamp \[1, 100]

```jsx
Weighted_Avg_Daily_ATR = (5 * Avg_Daily_ATR%_1_Days + 3 * Avg_Daily_ATR%_7_Days + 2 * Avg_Daily_ATR%_30_Days) / 10
VolFactorATR = Weighted_Avg_Daily_ATR / Daily_Close_price * 1000
VolFactor = VolFactorATR -> Clamp[1, 100]
```

UnderBorrowingConstantFactor: UBC (Constant Number)

OverBorrowingConstantFactor: OBC (Constant Number)

OverBorrowingLimitFactor: OBL → (Constant Number)

TotalOILimit: TOIL → (Default: 5X of Vault Balance)

TotalVaultBalance: TVB → (Vault Balance)

$$
BorrowingFeeAPR: \z=VolFactor \* UnderBorrowingConstantFactor \* (LongOI+ ShortOI)/\ TotalVaultBalance \Condition:(0< LongOI + ShortOI < TotalVaultBalance \* OverBorrowingLimitFactor)
$$

$$
z=VolFactor \* UnderBorrowingConstantFactor \* OverBorrowingLimitFactor + \VolFactor \* OverBorrowingConstantFactor \* \\(LongOI + ShortOI - TotalVaultBalance*OverBorrowingLimitFactor)/\ TotalVaultBalance \Condition:(LongOI + ShortOI > TotalVaultBalance*OverBorrowingLimitFactor)
$$

$$
BorrowingFeeAPR =Clamp\[L, U]
$$

Borrowing Fee Rate Per Year:

<table data-full-width="true"><thead><tr><th width="255">Currency</th><th width="159">VolFactorRange</th><th width="238">OverBorrowingLimitFactor</th><th width="284">UnderBorrowingConstantFactor</th><th width="263">OverBorrowingConstantFactor</th><th width="151">Clamp / L→APR</th><th width="153">Clamp / U→APR</th><th data-hidden>VolFactorDefault</th></tr></thead><tbody><tr><td>Group 1: BTC 、ETH</td><td>[1,10]</td><td>5</td><td>1/100</td><td>2/100</td><td>1%</td><td>25%</td><td>5</td></tr><tr><td>Group 2: ADA、AVAX、BCH、DOT、EOS、ETC、FIL、LINK、LTC、TRX、XRP、BTC(USDC)</td><td>[5,25]</td><td>5</td><td>2/100</td><td>4/100</td><td>10%</td><td>50%</td><td>10</td></tr><tr><td>Group 3: Top(50)</td><td>[5, 50]</td><td>5</td><td>4/100</td><td>8/100</td><td>20%</td><td>100%</td><td>20</td></tr></tbody></table>