diff --git a/src/PhpSpreadsheet/Calculation.php b/src/PhpSpreadsheet/Calculation.php
index d84932bc..062e2174 100644
--- a/src/PhpSpreadsheet/Calculation.php
+++ b/src/PhpSpreadsheet/Calculation.php
@@ -13,6 +13,7 @@ use PhpOffice\PhpSpreadsheet\Calculation\LookupRef;
 use PhpOffice\PhpSpreadsheet\Calculation\MathTrig;
 use PhpOffice\PhpSpreadsheet\Calculation\Statistical;
 use PhpOffice\PhpSpreadsheet\Calculation\TextData;
+use PhpOffice\PhpSpreadsheet\Calculation\Token\Stack;
 
 /**
  * Copyright (c) 2006 - 2016 PhpSpreadsheet.
@@ -2059,8 +2060,6 @@ class Calculation
 
     /**
      * Unset an instance of this class.
-     *
-     * @param Spreadsheet $spreadsheet Injected spreadsheet identifying the instance to unset
      */
     public function __destruct()
     {
@@ -2314,6 +2313,14 @@ class Calculation
         return false;
     }
 
+    /**
+     * @param string $fromSeparator
+     * @param string $toSeparator
+     * @param string $formula
+     * @param bool $inBraces
+     *
+     * @return string
+     */
     public static function translateSeparator($fromSeparator, $toSeparator, $formula, &$inBraces)
     {
         $strlen = mb_strlen($formula);
@@ -2657,6 +2664,12 @@ class Calculation
         return $result;
     }
 
+    /**
+     * @param string $cellReference
+     * @param mixed $cellValue
+     *
+     * @return bool
+     */
     public function getValueFromCache($cellReference, &$cellValue)
     {
         // Is calculation cacheing enabled?
@@ -2985,6 +2998,11 @@ class Calculation
         }
     }
 
+    /**
+     * @param string $formula
+     *
+     * @return string
+     */
     private function convertMatrixReferences($formula)
     {
         static $matrixReplaceFrom = ['{', ';', '}'];
@@ -3073,6 +3091,13 @@ class Calculation
     ];
 
     // Convert infix to postfix notation
+
+    /**
+     * @param string $formula
+     * @param Cell|null $pCell
+     *
+     * @return bool
+     */
     private function _parseFormula($formula, Cell $pCell = null)
     {
         if (($formula = $this->convertMatrixReferences(trim($formula))) === false) {
@@ -3094,7 +3119,7 @@ class Calculation
 
         //    Start with initialisation
         $index = 0;
-        $stack = new Calculation\Token\Stack();
+        $stack = new Stack();
         $output = [];
         $expectingOperator = false; //    We use this test in syntax-checking the expression to determine when a
                                                     //        - is a negation or + is a positive operator rather than an operation
@@ -3401,8 +3426,11 @@ class Calculation
     // evaluate postfix notation
 
     /**
-     * @param string $cellID
      * @param mixed $tokens
+     * @param string|null $cellID
+     * @param Cell|null $pCell
+     *
+     * @return bool
      */
     private function processTokenStack($tokens, $cellID = null, Cell $pCell = null)
     {
@@ -3414,7 +3442,7 @@ class Calculation
         //        so we store the parent cell collection so that we can re-attach it when necessary
         $pCellWorksheet = ($pCell !== null) ? $pCell->getWorksheet() : null;
         $pCellParent = ($pCell !== null) ? $pCell->getParent() : null;
-        $stack = new Calculation\Token\Stack();
+        $stack = new Stack();
 
         //    Loop through each token in turn
         foreach ($tokens as $tokenData) {
@@ -3811,7 +3839,17 @@ class Calculation
         return true;
     }
 
-    private function executeBinaryComparisonOperation($cellID, $operand1, $operand2, $operation, &$stack, $recursingArrays = false)
+    /**
+     * @param string|null $cellID
+     * @param mixed $operand1
+     * @param mixed $operand2
+     * @param string $operation
+     * @param Stack $stack
+     * @param bool $recursingArrays
+     *
+     * @return bool
+     */
+    private function executeBinaryComparisonOperation($cellID, $operand1, $operand2, $operation, Stack &$stack, $recursingArrays = false)
     {
         //    If we're dealing with matrix operations, we want a matrix result
         if ((is_array($operand1)) || (is_array($operand2))) {
@@ -3951,7 +3989,7 @@ class Calculation
 
     /**
      * @param string $matrixFunction
-     * @param mixed $cellID
+     * @param string|null $cellID
      * @param mixed $operand1
      * @param mixed $operand2
      * @param mixed $operation
diff --git a/src/PhpSpreadsheet/Calculation/Engineering.php b/src/PhpSpreadsheet/Calculation/Engineering.php
index 582c6cbd..8136fe68 100644
--- a/src/PhpSpreadsheet/Calculation/Engineering.php
+++ b/src/PhpSpreadsheet/Calculation/Engineering.php
@@ -2293,7 +2293,7 @@ class Engineering
      * Excel Function:
      *        IMSUM(complexNumber[,complexNumber[,...]])
      *
-     * @param string $complexNumbers Series of complex numbers to add
+     * @param string ...$complexNumbers Series of complex numbers to add
      *
      * @return string
      */
@@ -2333,7 +2333,7 @@ class Engineering
      * Excel Function:
      *        IMPRODUCT(complexNumber[,complexNumber[,...]])
      *
-     * @param string $complexNumbers Series of complex numbers to multiply
+     * @param string ...$complexNumbers Series of complex numbers to multiply
      *
      * @return string
      */
diff --git a/src/PhpSpreadsheet/Calculation/Logical.php b/src/PhpSpreadsheet/Calculation/Logical.php
index 5492cc6e..4db10945 100644
--- a/src/PhpSpreadsheet/Calculation/Logical.php
+++ b/src/PhpSpreadsheet/Calculation/Logical.php
@@ -80,7 +80,7 @@ class Logical
      *
      * @category Logical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return string|bool the logical AND of the arguments
      */
diff --git a/src/PhpSpreadsheet/Calculation/MathTrig.php b/src/PhpSpreadsheet/Calculation/MathTrig.php
index 25200205..f3bcaedb 100644
--- a/src/PhpSpreadsheet/Calculation/MathTrig.php
+++ b/src/PhpSpreadsheet/Calculation/MathTrig.php
@@ -347,7 +347,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return int Greatest Common Divisor
      */
@@ -456,7 +456,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return int Lowest Common Multiplier
      */
@@ -859,7 +859,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -899,7 +899,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1185,7 +1185,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1306,7 +1306,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1351,7 +1351,7 @@ class MathTrig
      *
      * @category Mathematical and Trigonometric Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
diff --git a/src/PhpSpreadsheet/Calculation/Statistical.php b/src/PhpSpreadsheet/Calculation/Statistical.php
index fc5cdbb3..954dfe3c 100644
--- a/src/PhpSpreadsheet/Calculation/Statistical.php
+++ b/src/PhpSpreadsheet/Calculation/Statistical.php
@@ -720,7 +720,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -771,7 +771,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -814,7 +814,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1207,7 +1207,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return int
      */
@@ -1241,7 +1241,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return int
      */
@@ -1271,7 +1271,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return int
      */
@@ -1491,7 +1491,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1785,7 +1785,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1851,7 +1851,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -1967,7 +1967,7 @@ class Statistical
      * kurtosis indicates a relatively peaked distribution. Negative kurtosis indicates a
      * relatively flat distribution.
      *
-     * @param array Data Series
+     * @param array ...$args Data Series
      *
      * @return float
      */
@@ -2249,7 +2249,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -2285,7 +2285,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -2368,7 +2368,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -2412,7 +2412,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -2448,7 +2448,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -2568,7 +2568,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3016,7 +3016,7 @@ class Statistical
      * asymmetric tail extending toward more positive values. Negative skewness indicates a
      * distribution with an asymmetric tail extending toward more negative values.
      *
-     * @param array Data Series
+     * @param array ...$args Data Series
      *
      * @return float
      */
@@ -3161,7 +3161,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3210,7 +3210,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3262,7 +3262,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3309,7 +3309,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3599,7 +3599,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3643,7 +3643,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3696,7 +3696,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */
@@ -3741,7 +3741,7 @@ class Statistical
      *
      * @category Statistical Functions
      *
-     * @param mixed $args Data values
+     * @param mixed ...$args Data values
      *
      * @return float
      */