Formulas and parameters value in Wing project

The collateral factor is a parameter that limits the maximum amount a user can borrow using a specific asset as collateral. Each asset in the Flash Pool has specific values related to their risk, which influences how they are loaned and borrowed. The calibration of the parameters for Wing Project is more aggressive as the Wing ecosystem is mature with some educated users and liquidators. The table below shows the Collateral Factor of each asset.

Asset Type | Collateral Factor |

ONTd | 60% |

pwBTC | 75% |

prenBTC | 75% |

pUSDC | 80% |

pETH | 80% |

pDAI | 80% |

pUSDT | 80% |

pSUSD | 80% |

pNEO | 50% |

pUNI | 65% |

WING | 40% |

ONG | 40% |

pYFI | 55% |

Asset Type | Collateral Factor |

pWING | 40% |

oneWING | 85% |

pONT | 60% |

USDT | 80% |

ETH | 80% |

WBTC | 75% |

Asset Type | Collateral Factor |

WING | 50% |

ONTK | 65% |

OKT | 70% |

USDT | 80% |

USDC | 80% |

BTCK | 70% |

ETHK | 70% |

DOTK | 65% |

OKB | 70% |

LINKK | 65% |

SUSHIK | 50% |

UNIK | 60% |

DAIK | 75% |

According to the Collateral Factor for each asset, users can calculate the maximum asset value that can be borrowed.

*For example, User A supplied $1,000 worth pETH, then the maximum asset value can be borrowed for User A is $1,000*80% = $800.*

APR is the abbreviation for Annual Percentage Rate, which is the annual rate of interest charged to borrowers.

In WIP-15, a kink point was introduced to the interest rate model.

The new interest rate model before and after the kink point uses different formulas. The interest rate growth before the kink point is relatively slow, compared to a rapid increase after the kink point.

We set the capital utilization rate to "U" and the interest rate to "R" so that when the capital utilization rate is "U", the corresponding interest rate will be "R." The kink point (k) will have a capital utilization rate of "Uk." When the basic interest is R0, the kink point intersection will be R0+Rk, and the interest when the capital utilization rate is 100% is R0+Rk+R100.

Formulas:

If U<Uk: R=R0+U/Uk*Rk

If U≥Uk: R=R0+Rk+(U-Uk)/(1-Uk)*R100

Model Parameters:

R0=1%

Rk=7%

R100=100%

Uk=80%

*For example, *

*when U=20%, R=1%+20%/80%*7%=2.75%,*

*and when U=90%, R=1%+7%+(90%-80%)/(1-80%)*100%=58%.*

Reserve factor is the proportion of borrow interests reserved. Currently, the number is 15% for all assets in Flash Pool.

If a borrower's address reaches 100% of its borrow limit, the borrower's collateral assets will be liquidated. Liquidators can buy collateral assets at the discounts listed below and thus earn liquidation bonus.

Asset Type | Liquidation Bonus |

ONTd | 8% |

pwBTC | 8% |

prenBTC | 8% |

pUSDC | 5% |

pETH | 8% |

pDAI | 5% |

pUSDT | 5% |

pSUSD | 5% |

pNEO | 8% |

pUNI | 8% |

WING | 8% |

ONG | 8% |

pYFI | 8% |

Asset Type | Liquidation Bonus |

pWING | 8% |

oneWING | 5% |

pONT | 8% |

USDT | 5% |

ETH | 8% |

WBTC | 8% |

Asset Type | Liquidation Bonus |

WING | 8% |

ONTK | 8% |

OKT | 8% |

USDT | 5% |

USDC | 5% |

BTCK | 8% |

ETHK | 8% |

DOTK | 8% |

OKB | 8% |

LINKK | 8% |

SUSHIK | 8% |

UNIK | 8% |

DAIK | 5% |