PremiumsAccount

The risk modules are grouped in premiums accounts that keep track of the pure premiums (active and earned) their policies. The responsibility of these contracts is to keep track of the premiums and release the payouts. When premiums are exhausted (losses more than expected), they borrow money from the eTokens to cover the payouts. This money will be repaid when/if later the premiums account has a surplus (losses less than expected).

Roles

The specific roles and functions of the contract are as follows:

( * ) Global means that the role can be delegated to a user at the protocol level (for all components) or only for a specific component. Non-global roles can only be granted for a specific component.

Interactions

Parameters

Packed parameters

To save gas, the parameters are stored in a packed struct that fits in 256bits (a word in the EVM). This is not visible externally, but put's limits on the precision of the parameters. The wad ones, have 4 decimals as precision, so 1.12345 will be truncated to 1.1234.

Events

WonPremiumsInOut

event WonPremiumsInOut(bool moneyIn, uint256 value)

Premiums can come in (for "free", without liability) with receiveGrant. And can come out (withdrawed to treasury) with withdrawWonPremiums

External Methods

policyCreated

function policyCreated(struct Policy.PolicyData policy) external

Adds a policy to the PremiumsAccount. Stores the pure premiums and locks the aditional funds from junior and senior eTokens.

Requirements:

• Must be called by policyPool()

Events:

• {EToken-SCRLocked}

policyResolvedWithPayout

function policyResolvedWithPayout(address policyHolder, struct Policy.PolicyData policy, uint256 payout) external

The PremiumsAccount is notified that the policy was resolved and issues the payout to the policyHolder.

Requirements:

• Must be called by policyPool()

Events:

• {ERC20-Transfer}: to == policyHolder, amount == payout

• {EToken-InternalLoan}: optional, if a loan needs to be taken

• {EToken-SCRUnlocked}

policyExpired

function policyExpired(struct Policy.PolicyData policy) external

The PremiumsAccount is notified that the policy has expired, unlocks the SCR and earns the pure premium.

Requirements:

• Must be called by policyPool()

Events:

• {ERC20-Transfer}: to == policyHolder, amount == payout

• {EToken-InternalLoanRepaid}: optional, if a loan was taken before

seniorEtk

function seniorEtk() external view returns (contract IEToken)

The senior eToken, the secondary source of solvency, used if the premiums account is exhausted and junior too

juniorEtk

function juniorEtk() external view returns (contract IEToken)

The junior eToken, the primary source of solvency, used if the premiums account is exhausted.

purePremiums

function purePremiums() external view returns (uint256)

The total amount of premiums hold by this PremiumsAccount

activePurePremiums

function activePurePremiums() external view returns (uint256)

Returns the total amount of pure premiums that were collected by the active policies of the risk modules linked to this PremiumsAccount.

wonPurePremiums

function wonPurePremiums() external view returns (uint256)

Returns the surplus between pure premiums collected and payouts of finalized policies. Returns 0 if no surplus or deficit.

borrowedActivePP

function borrowedActivePP() external view returns (uint256)

Returns the amount of active pure premiums that was used to cover payouts of finalized policies (in excess of collected pure premiums). This is limited by _maxDeficit().

surplus

function surplus() external view returns (int256)

Returns the surplus between pure premiums collected and payouts of finalized policies. Losses where more than premiums collected, returns a negative number that indicates the amount of the active pure premiums that was used to cover finalized premiums.

deficitRatio

function deficitRatio() public view returns (uint256)

Returns the percentage of the active pure premiums that can be used to cover losses of finalized policies.

setDeficitRatio

function setDeficitRatio(uint256 newRatio, bool adjustment) external

Changes the deficitRatio parameter.

Requirements:

• onlyGlobalOrComponentRole(LEVEL2_ROLE)

Events:

• Emits GovernanceAction with action = setDeficitRatio or setDeficitRatioWithAdjustment if an adjustment was made.

receiveGrant

function receiveGrant(uint256 amount) external

Endpoint to receive "free money" and inject that money into the premium pool.

Can be used for example if the PolicyPool subscribes an excess loss policy with other company.

Requirements:

• The sender needs to approve the spending of currency() by this contract.

Events:

• Emits {WonPremiumsInOut} with moneyIn = true

withdrawWonPremiums

function withdrawWonPremiums(uint256 amount, address destination) external returns (uint256)

Withdraws excess premiums (surplus) to the destination.

This might be needed in some cases for example if we are deprecating the protocol or the excess premiums are needed to compensate something. Shouldn't be used. Can be disabled revoking role WITHDRAW_WON_PREMIUMS_ROLE

Requirements:

• onlyGlobalOrComponentRole(WITHDRAW_WON_PREMIUMS_ROLE)

• _surplus > 0

Events:

• Emits {WonPremiumsInOut} with moneyIn = false

Inherited from Reserve

assetManager

function assetManager() public view virtual returns (contract IAssetManager)

Returns the address of the asset manager for this reserve. The asset manager is the contract that manages the funds to generate additional yields. Can be address(0) if no asset manager has been set.

setAssetManager

function setAssetManager(contract IAssetManager newAM, bool force) external

Sets the asset manager for this reserve. If the reserve had previously an asset manager, it will deinvest all the funds, making all of the liquid in the reserve balance.

Requirements:

• The caller must have been granted of global or component roles GUARDIAN_ROLE or LEVEL1_ROLE.

Events:

• Emits ComponentChanged with action setAssetManager or setAssetManagerForced

rebalance

function rebalance() public

Calls {IAssetManager-rebalance} of the assigned asset manager (fails if no asset manager). This operation is intended to give the opportunity to rebalance the liquid and invested for better returns and/or gas optimization.

• Emits {IAssetManager-MoneyInvested} or {IAssetManager-MoneyDeinvested}

recordEarnings

function recordEarnings() public

Calls {IAssetManager-recordEarnings} of the assigned asset manager (fails if no asset manager). The asset manager will return the earnings since last time the earnings where recorded. It then calls _assetEarnings to reflect the earnings in the way defined for each reserve.

• Emits {IAssetManager-EarningsRecorded}

checkpoint

function checkpoint() external

Function that calls both recordEarnings() and rebalance() (in that order). Usually scheduled to run once a day by a keeper or crontask.

forwardToAssetManager

function forwardToAssetManager(bytes functionCall) external returns (bytes)

This function allows to call custom functions of the asset manager (for example for setting parameters). This functions will be called with delegatecall, in the context of the reserve.

Requirements:

• The caller must have been granted of global or component roles LEVEL2ROLE.