Compute Fee Inside for Range - Exponent Docs

The MarketThree.computeFeeInsideForRange() static method computes the fee growth that has occurred inside a specified tick range. This is essential for calculating fees earned by liquidity positions.

Usage

import { MarketThree } from "@exponent-labs/exponent-sdk";

// Compute fee growth inside a tick range
const { insideSy, insidePt } = MarketThree.computeFeeInsideForRange({
  currentTickPrice: market.state.financials.currentSpotPrice,
  lowerTickPrice: 1.05,  // Lower bound: 5% APY
  upperTickPrice: 1.10,   // Upper bound: 10% APY
  feeGrowthIndexGlobalPt: market.state.financials.feeGrowthIndexGlobalPt,
  feeGrowthIndexGlobalSy: market.state.financials.feeGrowthIndexGlobalSy,
  lowerTickOutsidePt: lowerTick.feeGrowthOutsidePt,
  lowerTickOutsideSy: lowerTick.feeGrowthOutsideSy,
  upperTickOutsidePt: upperTick.feeGrowthOutsidePt,
  upperTickOutsideSy: upperTick.feeGrowthOutsideSy,
});

console.log("SY fee growth inside range:", insideSy);
console.log("PT fee growth inside range:", insidePt);

Parameters

Parameter	Type	Required	Description
`currentTickPrice`	`number`	Yes	Current market price in format of 1 + percentage / 100
`lowerTickPrice`	`number`	Yes	Lower tick boundary price in format of 1 + percentage / 100
`upperTickPrice`	`number`	Yes	Upper tick boundary price in format of 1 + percentage / 100
`feeGrowthIndexGlobalPt`	`bigint`	Yes	Global PT fee growth index
`feeGrowthIndexGlobalSy`	`bigint`	Yes	Global SY fee growth index
`lowerTickOutsidePt`	`bigint`	Yes	PT fee growth outside the lower tick
`lowerTickOutsideSy`	`bigint`	Yes	SY fee growth outside the lower tick
`upperTickOutsidePt`	`bigint`	Yes	PT fee growth outside the upper tick
`upperTickOutsideSy`	`bigint`	Yes	SY fee growth outside the upper tick

Returns

Returns an object with:

{
  insideSy: bigint;
  insidePt: bigint;
}

Property	Type	Description
`insideSy`	`bigint`	SY fee growth that occurred inside the tick range
`insidePt`	`bigint`	PT fee growth that occurred inside the tick range

Calculation Logic

The method implements the Uniswap V3 formula for computing fee growth inside a range:

If current price < lower price: inside = outside(lower) - outside(upper)
If current price >= upper price: inside = outside(upper) - outside(lower)
If current price is inside range: inside = global - outside(lower) - outside(upper)

This allows tracking of fees earned specifically within the position’s active range.