diff --git a/unitTests/Classes/PHPExcel/CalculationTest.php b/unitTests/Classes/PHPExcel/CalculationTest.php
index 8f8ce7e0..1a510a02 100644
--- a/unitTests/Classes/PHPExcel/CalculationTest.php
+++ b/unitTests/Classes/PHPExcel/CalculationTest.php
@@ -25,6 +25,8 @@ class CalculationTest extends PHPUnit_Framework_TestCase
         PHPExcel_Calculation_Functions::setCompatibilityMode(PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE);
         $resultOpenOffice = \PHPExcel_Calculation::getInstance()->_calculateFormulaValue($formula);
         $this->assertEquals($expectedResultOpenOffice, $resultOpenOffice, 'should be OpenOffice compatible');
+
+        PHPExcel_Calculation_Functions::setCompatibilityMode(PHPExcel_Calculation_Functions::COMPATIBILITY_EXCEL);
     }
 
     public function providerBinaryComparisonOperation()