diff --git a/README.md b/README.md
index fa7869c..7f28079 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,8 @@ composer require holicz/pvgis
 * PHP >= 7.4
 
 # Usage
+
+## Basic usage
 ```php
 <?php
 
@@ -29,3 +31,11 @@ foreach ($electricityProduction->getMonthlyProductions() as $monthlyProduction)
     $monthlyProduction->getProduction();
 }
 ``` 
+
+## Using multiplier
+If you for example know that you have six solar panels and the production is 1.86x time more bigger than the PVGIS
+result you should use the multiplier method
+
+```php
+$electricityProduction->multiply(1.86);
+```
diff --git a/src/Model/ElectricityProduction.php b/src/Model/ElectricityProduction.php
index f519cd4..9e8ad10 100644
--- a/src/Model/ElectricityProduction.php
+++ b/src/Model/ElectricityProduction.php
@@ -25,6 +25,22 @@ public function __clone()
         $this->monthlyProductions = $monthlyProductions;
     }
 
+    /**
+     * Method to multiply the results by constant
+     * Useful if you know how much more powerful your solar panels are than the PVGIS result
+     *
+     * @param float $multiplier
+     */
+    public function multiply(float $multiplier): void
+    {
+        $this->yearlyProduction = round($this->yearlyProduction * $multiplier, 2);
+
+        foreach ($this->monthlyProductions as $monthlyProduction) {
+            $monthlyProduction->multiply($multiplier);
+        }
+    }
+
+
     public function addMonthlyProduction(int $month, float $production): self
     {
         $this->monthlyProductions[] = new MonthlyProduction($month, $production);
diff --git a/src/Model/MonthlyProduction.php b/src/Model/MonthlyProduction.php
index 6a01440..e5669b4 100644
--- a/src/Model/MonthlyProduction.php
+++ b/src/Model/MonthlyProduction.php
@@ -15,6 +15,11 @@ public function __construct(int $month, float $production)
         $this->production = $production;
     }
 
+    public function multiply(float $multiplier): void
+    {
+        $this->production = round($this->production * $multiplier, 2);
+    }
+
     public function getMonth(): int
     {
         return $this->month;