Add APR calc

schema.graphql

@@ -311,6 +311,16 @@ type BeefyCLVault @entity {
   "Amount of native token charged as strategist fee incentive in USD"
   cumulativeStrategistFeeCollectedUSD: BigDecimal!
 
+  "The last time the fees were collected. Used to calculate the vault APR."
+  lastCollectedFeeTimestamp: BigInt!
+  """
+  The current APR of the vault.
+  This is calculated as the amound of fees collected since the last fee collection event
+  divided by the TVL in the vault at the time of the fee collection event, and
+  annualized by the time since the last fee collection event.
+  """
+  annualPercentageRateFromLastCollection: BigDecimal!
+
   "All investors positions in the vault"
   positions: [InvestorPosition!]! @derivedFrom(field: "vault")
 
@@ -419,6 +429,14 @@ type BeefyCLVaultSnapshot implements Snapshot @entity {
   protocolFeeCollectedUSD: BigDecimal!
   "Amount of native token charged as strategist fee incentive in USD"
   strategistFeeCollectedUSD: BigDecimal!
+
+  """
+  The current APR of the vault.
+  This is calculated as the amound of fees collected since the last fee collection event
+  divided by the TVL in the vault at the time of the fee collection event, and
+  annualized by the time since the last fee collection event.
+  """
+  annualPercentageRateFromLastCollection: BigDecimal!
 }
 
 """

src/entity/vault.ts

@@ -1,4 +1,4 @@
-import { BigInt, Bytes } from "@graphprotocol/graph-ts"
+import { BigDecimal, BigInt, Bytes } from "@graphprotocol/graph-ts"
 import { BeefyCLStrategy, BeefyCLVault, BeefyCLVaultSnapshot } from "../../generated/schema"
 import { ADDRESS_ZERO } from "../utils/address"
 import { ZERO_BD } from "../utils/decimal"
@@ -53,6 +53,8 @@ export function getBeefyCLVault(vaultAddress: Bytes): BeefyCLVault {
     vault.cumulativeHarvesterFeeCollectedUSD = ZERO_BD
     vault.cumulativeProtocolFeeCollectedUSD = ZERO_BD
     vault.cumulativeStrategistFeeCollectedUSD = ZERO_BD
+    vault.lastCollectedFeeTimestamp = BigInt.fromI32(0)
+    vault.annualPercentageRateFromLastCollection = ZERO_BD
   }
   return vault
 }
@@ -106,6 +108,7 @@ export function getBeefyCLVaultSnapshot(vault: BeefyCLVault, timestamp: BigInt,
     snapshot.harvesterFeeCollectedUSD = ZERO_BD
     snapshot.protocolFeeCollectedUSD = ZERO_BD
     snapshot.strategistFeeCollectedUSD = ZERO_BD
+    snapshot.annualPercentageRateFromLastCollection = ZERO_BD
   }
 
   // copy non-reseting values from the previous snapshot to the new snapshot

src/vault-compound.ts

@@ -10,7 +10,7 @@ import { BeefyCLVaultHarvestEvent, BeefyCLVaultUnderlyingFeesCollectedEvent } fr
 import { getEventIdentifier } from "./utils/event"
 import { getToken } from "./entity/token"
 import { ONE_BD, ZERO_BD, tokenAmountToDecimal, decimalToTokenAmount } from "./utils/decimal"
-import { SNAPSHOT_PERIODS } from "./utils/time"
+import { SNAPSHOT_PERIODS, YEAR } from "./utils/time"
 import { getBeefyCLProtocol, getBeefyCLProtocolSnapshot } from "./entity/protocol"
 import { getInvestorPositionSnapshot } from "./entity/position"
 import { getInvestor, getInvestorSnapshot } from "./entity/investor"
@@ -339,6 +339,12 @@ export function handleStrategyClaimedFees(event: ClaimedFeesEvent): void {
   vault.underlyingAmount0USD = vault.underlyingAmount0.times(token0PriceInUSD)
   vault.underlyingAmount1USD = vault.underlyingAmount1.times(token1PriceInUSD)
   vault.totalValueLockedUSD = vault.underlyingAmount0USD.plus(vault.underlyingAmount1USD)
+  const feesEarnedSinceLastCollection = collect.collectedValueUSD
+  const feesEarnedOverSeconds = event.block.timestamp.minus(vault.lastCollectedFeeTimestamp)
+  const feesPerSecond = feesEarnedSinceLastCollection.div(feesEarnedOverSeconds.toBigDecimal())
+  const feesPerYear = feesPerSecond.times(YEAR.toBigDecimal())
+  vault.annualPercentageRateFromLastCollection = feesPerYear.div(vault.totalValueLockedUSD)
+  vault.lastCollectedFeeTimestamp = event.block.timestamp
   vault.save()
   for (let i = 0; i < periods.length; i++) {
     log.debug("handleStrategyChargedFees: updating vault snapshot for vault {} and period {}", [
@@ -357,6 +363,7 @@ export function handleStrategyClaimedFees(event: ClaimedFeesEvent): void {
     vaultSnapshot.underlyingAmount0USD = vault.underlyingAmount0USD
     vaultSnapshot.underlyingAmount1USD = vault.underlyingAmount1USD
     vaultSnapshot.totalValueLockedUSD = vault.totalValueLockedUSD
+    vaultSnapshot.annualPercentageRateFromLastCollection = vault.annualPercentageRateFromLastCollection
     vaultSnapshot.save()
   }