diff --git a/src/PhpSpreadsheet/Calculation/LookupRef.php b/src/PhpSpreadsheet/Calculation/LookupRef.php
index 359fa164..5e76633b 100644
--- a/src/PhpSpreadsheet/Calculation/LookupRef.php
+++ b/src/PhpSpreadsheet/Calculation/LookupRef.php
@@ -768,7 +768,7 @@ class LookupRef
         } else {
             $f = array_keys($lookup_array);
             $firstRow = array_pop($f);
-            if ((!is_array($lookup_array[$firstRow])) || ($index_number > count($lookup_array[$firstRow]))) {
+            if ((!is_array($lookup_array[$firstRow])) || ($index_number - 1 > count($lookup_array[$firstRow]))) {
                 return Functions::REF();
             } else {
                 $columnKeys = array_keys($lookup_array[$firstRow]);
@@ -781,7 +781,6 @@ class LookupRef
         if (!$not_exact_match) {
             $firstRowH = asort($lookup_array[$firstColumn]);
         }
-
         $rowNumber = $rowValue = false;
         foreach ($lookup_array[$firstColumn] as $rowKey => $rowData) {
             if ((is_numeric($lookup_value) && is_numeric($rowData) && ($rowData > $lookup_value)) ||
diff --git a/unitTests/Classes/src/Calculation/LookupRefTest.php b/unitTests/Classes/src/Calculation/LookupRefTest.php
index fdf2ab43..43a71088 100644
--- a/unitTests/Classes/src/Calculation/LookupRefTest.php
+++ b/unitTests/Classes/src/Calculation/LookupRefTest.php
@@ -4,6 +4,10 @@ namespace PHPExcel\Calculation;
 
 require_once 'testDataFileIterator.php';
 
+/**
+ * Class LookupRefTest
+ * @package PHPExcel\Calculation
+ */
 class LookupRefTest extends \PHPUnit_Framework_TestCase
 {
 
diff --git a/unitTests/rawTestData/Calculation/LookupRef/VLOOKUP.data b/unitTests/rawTestData/Calculation/LookupRef/VLOOKUP.data
index 8fefc6cc..8466d4f7 100644
--- a/unitTests/rawTestData/Calculation/LookupRef/VLOOKUP.data
+++ b/unitTests/rawTestData/Calculation/LookupRef/VLOOKUP.data
@@ -1,4 +1,4 @@
-1,		{"Density"|"Viscosity"|"Temperature";0.457|3.55|500;0.525|3.25|400;0.616|2.93|300;0.675|2.75|250;0.746|2.57|200;0.835|2.38|150;0.946|2.17|100;1.09|1.95|50;1.29|1.71|0},	2,	FALSE,	2.17
+1,		{"Density"|"Viscosity"|"Temperature";0.457|3.55|500;0.525|3.25|400;0.616|2.93|300;0.675|2.75|250;0.746|2.57|200;0.835|2.38|150;0.946|2.17|100;1.09|1.95|50;1.29|1.71|0},	2,	FALSE,	"#N/A"
 1,		{"Density"|"Viscosity"|"Temperature";0.457|3.55|500;0.525|3.25|400;0.616|2.93|300;0.675|2.75|250;0.746|2.57|200;0.835|2.38|150;0.946|2.17|100;1.09|1.95|50;1.29|1.71|0},	3,	TRUE,	100
 .7,		{"Density"|"Viscosity"|"Temperature";0.457|3.55|500;0.525|3.25|400;0.616|2.93|300;0.675|2.75|250;0.746|2.57|200;0.835|2.38|150;0.946|2.17|100;1.09|1.95|50;1.29|1.71|0},	3,	FALSE,	"#N/A"
 0.1,		{"Density"|"Viscosity"|"Temperature";0.457|3.55|500;0.525|3.25|400;0.616|2.93|300;0.675|2.75|250;0.746|2.57|200;0.835|2.38|150;0.946|2.17|100;1.09|1.95|50;1.29|1.71|0},	2,	TRUE,	"#N/A"