diff --git a/contracts/libraries/PercentageMath.sol b/contracts/libraries/PercentageMath.sol
index 0ef4bea4..846fb518 100644
--- a/contracts/libraries/PercentageMath.sol
+++ b/contracts/libraries/PercentageMath.sol
@@ -6,8 +6,9 @@ import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 /**
  * @title PercentageMath library
  * @author Aave
- * @notice Provides functions to calculate percentages. Percentages needs to be defined by default with 2 decimals of precision (100.00)
- * @dev Operations are rounded up
+ * @notice Provides functions to calculate percentages.
+ * @dev Percentages are defined by default with 2 decimals of precision (100.00). The precision is indicated by PERCENTAGE_FACTOR
+ * @dev Operations are rounded half up
  **/
 
 library PercentageMath {
@@ -16,13 +17,25 @@ library PercentageMath {
   uint256 constant PERCENTAGE_FACTOR = 1e4; //percentage plus two decimals
   uint256 constant HALF_PERCENT = PERCENTAGE_FACTOR / 2;
 
-  function percentMul(uint256 value, uint256 percentage) internal pure returns (uint256) {
-    return HALF_PERCENT.add(value.mul(percentage)).div(PERCENTAGE_FACTOR);
+  /**
+   * @dev executes a percentage multiplication
+   * @param _value the value of which the percentage needs to be calculated
+   * @param _percentage the percentage of the value to be calculated
+   * @return the _percentage of _value
+   **/
+  function percentMul(uint256 _value, uint256 _percentage) internal pure returns (uint256) {
+    return HALF_PERCENT.add(_value.mul(_percentage)).div(PERCENTAGE_FACTOR);
   }
 
-  function percentDiv(uint256 value, uint256 percentage) internal pure returns (uint256) {
-    uint256 halfPercentage = percentage / 2;
+  /**
+   * @dev executes a percentage division
+   * @param _value the value of which the percentage needs to be calculated
+   * @param _percentage the percentage of the value to be calculated
+   * @return the _value divided the _percentage
+   **/
+  function percentDiv(uint256 _value, uint256 _percentage) internal pure returns (uint256) {
+    uint256 halfPercentage = _percentage / 2;
 
-    return halfPercentage.add(value.mul(PERCENTAGE_FACTOR)).div(percentage);
+    return halfPercentage.add(_value.mul(PERCENTAGE_FACTOR)).div(_percentage);
   }
 }