diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index e9a33fc8..e07db455 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -825,16 +825,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/LookupRef.php
 
-		-
-			message: "#^Call to function is_bool\\(\\) with float\\|int\\|\\(string&numeric\\) will always evaluate to false\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/LookupRef.php
-
-		-
-			message: "#^Cannot call method getCell\\(\\) on PhpOffice\\\\PhpSpreadsheet\\\\Worksheet\\\\Worksheet\\|null\\.$#"
-			count: 2
-			path: src/PhpSpreadsheet/Calculation/LookupRef.php
-
 		-
 			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\LookupRef\\\\Address\\:\\:sheetName\\(\\) has no return typehint specified\\.$#"
 			count: 1
diff --git a/src/PhpSpreadsheet/Calculation/Calculation.php b/src/PhpSpreadsheet/Calculation/Calculation.php
index abd997a3..35769434 100644
--- a/src/PhpSpreadsheet/Calculation/Calculation.php
+++ b/src/PhpSpreadsheet/Calculation/Calculation.php
@@ -531,7 +531,7 @@ class Calculation
         ],
         'CHOOSE' => [
             'category' => Category::CATEGORY_LOOKUP_AND_REFERENCE,
-            'functionCall' => [LookupRef::class, 'CHOOSE'],
+            'functionCall' => [LookupRef\Selection::class, 'CHOOSE'],
             'argumentCount' => '2+',
         ],
         'CLEAN' => [
@@ -793,7 +793,7 @@ class Calculation
         ],
         'DB' => [
             'category' => Category::CATEGORY_FINANCIAL,
-            'functionCall' => [Financial::class, 'DB'],
+            'functionCall' => [Financial\Depreciation::class, 'DB'],
             'argumentCount' => '4,5',
         ],
         'DBCS' => [
@@ -813,7 +813,7 @@ class Calculation
         ],
         'DDB' => [
             'category' => Category::CATEGORY_FINANCIAL,
-            'functionCall' => [Financial::class, 'DDB'],
+            'functionCall' => [Financial\Depreciation::class, 'DDB'],
             'argumentCount' => '4,5',
         ],
         'DEC2BIN' => [
@@ -1118,7 +1118,7 @@ class Calculation
         ],
         'FORMULATEXT' => [
             'category' => Category::CATEGORY_LOOKUP_AND_REFERENCE,
-            'functionCall' => [LookupRef::class, 'FORMULATEXT'],
+            'functionCall' => [LookupRef\Formula::class, 'text'],
             'argumentCount' => '1',
             'passCellReference' => true,
             'passByReference' => [true],
@@ -1245,7 +1245,7 @@ class Calculation
         ],
         'HYPERLINK' => [
             'category' => Category::CATEGORY_LOOKUP_AND_REFERENCE,
-            'functionCall' => [LookupRef::class, 'HYPERLINK'],
+            'functionCall' => [LookupRef\Hyperlink::class, 'set'],
             'argumentCount' => '1,2',
             'passCellReference' => true,
         ],
@@ -2604,7 +2604,7 @@ class Calculation
         ],
         'XIRR' => [
             'category' => Category::CATEGORY_FINANCIAL,
-            'functionCall' => [Financial::class, 'XIRR'],
+            'functionCall' => [Financial\CashFlow\Variable\NonPeriodic::class, 'rate'],
             'argumentCount' => '2,3',
         ],
         'XLOOKUP' => [
@@ -2614,7 +2614,7 @@ class Calculation
         ],
         'XNPV' => [
             'category' => Category::CATEGORY_FINANCIAL,
-            'functionCall' => [Financial::class, 'XNPV'],
+            'functionCall' => [Financial\CashFlow\Variable\NonPeriodic::class, 'presentValue'],
             'argumentCount' => '3',
         ],
         'XMATCH' => [
diff --git a/src/PhpSpreadsheet/Calculation/DateTime.php b/src/PhpSpreadsheet/Calculation/DateTime.php
index c0a38f56..4959c957 100644
--- a/src/PhpSpreadsheet/Calculation/DateTime.php
+++ b/src/PhpSpreadsheet/Calculation/DateTime.php
@@ -4,6 +4,9 @@ namespace PhpOffice\PhpSpreadsheet\Calculation;
 
 use DateTimeInterface;
 
+/**
+ * @deprecated 1.18.0
+ */
 class DateTime
 {
     /**
diff --git a/src/PhpSpreadsheet/Calculation/LookupRef.php b/src/PhpSpreadsheet/Calculation/LookupRef.php
index 5adf4f09..c213396d 100644
--- a/src/PhpSpreadsheet/Calculation/LookupRef.php
+++ b/src/PhpSpreadsheet/Calculation/LookupRef.php
@@ -13,6 +13,9 @@ use PhpOffice\PhpSpreadsheet\Calculation\LookupRef\VLookup;
 use PhpOffice\PhpSpreadsheet\Cell\Cell;
 use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 
+/**
+ * @deprecated 1.18.0
+ */
 class LookupRef
 {
     /**
@@ -25,7 +28,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the cell() method in the LookupRef\Address class instead
+     * @see LookupRef\Address::cell()
+     *      Use the cell() method in the LookupRef\Address class instead
      *
      * @param mixed $row Row number to use in the cell reference
      * @param mixed $column Column number to use in the cell reference
@@ -61,11 +65,12 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the COLUMN() method in the LookupRef\RowColumnInformation class instead
+     * @see LookupRef\RowColumnInformation::COLUMN()
+     *      Use the COLUMN() method in the LookupRef\RowColumnInformation class instead
      *
      * @param null|array|string $cellAddress A reference to a range of cells for which you want the column numbers
      *
-     * @return int|int[]
+     * @return int|int[]|string
      */
     public static function COLUMN($cellAddress = null, ?Cell $cell = null)
     {
@@ -82,7 +87,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the COLUMNS() method in the LookupRef\RowColumnInformation class instead
+     * @see LookupRef\RowColumnInformation::COLUMNS()
+     *      Use the COLUMNS() method in the LookupRef\RowColumnInformation class instead
      *
      * @param null|array|string $cellAddress An array or array formula, or a reference to a range of cells
      *                                          for which you want the number of columns
@@ -109,7 +115,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the ROW() method in the LookupRef\RowColumnInformation class instead
+     * @see LookupRef\RowColumnInformation::ROW()
+     *      Use the ROW() method in the LookupRef\RowColumnInformation class instead
      *
      * @param null|array|string $cellAddress A reference to a range of cells for which you want the row numbers
      *
@@ -130,7 +137,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the ROWS() method in the LookupRef\RowColumnInformation class instead
+     * @see LookupRef\RowColumnInformation::ROWS()
+     *      Use the ROWS() method in the LookupRef\RowColumnInformation class instead
      *
      * @param null|array|string $cellAddress An array or array formula, or a reference to a range of cells
      *                                          for which you want the number of rows
@@ -148,29 +156,20 @@ class LookupRef
      * Excel Function:
      *        =HYPERLINK(linkURL,displayName)
      *
+     * @Deprecated 1.18.0
+     *
+     * @see LookupRef\Hyperlink::set()
+     *      Use the set() method in the LookupRef\Hyperlink class instead
+     *
      * @param mixed $linkURL Expect string. Value to check, is also the value returned when no error
      * @param mixed $displayName Expect string. Value to return when testValue is an error condition
      * @param Cell $pCell The cell to set the hyperlink in
      *
-     * @return mixed The value of $displayName (or $linkURL if $displayName was blank)
+     * @return string The value of $displayName (or $linkURL if $displayName was blank)
      */
     public static function HYPERLINK($linkURL = '', $displayName = null, ?Cell $pCell = null)
     {
-        $linkURL = ($linkURL === null) ? '' : Functions::flattenSingleValue($linkURL);
-        $displayName = ($displayName === null) ? '' : Functions::flattenSingleValue($displayName);
-
-        if ((!is_object($pCell)) || (trim($linkURL) == '')) {
-            return Functions::REF();
-        }
-
-        if ((is_object($displayName)) || trim($displayName) == '') {
-            $displayName = $linkURL;
-        }
-
-        $pCell->getHyperlink()->setUrl($linkURL);
-        $pCell->getHyperlink()->setTooltip($displayName);
-
-        return $displayName;
+        return LookupRef\Hyperlink::set($linkURL, $displayName, $pCell);
     }
 
     /**
@@ -184,7 +183,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the INDIRECT() method in the LookupRef\Indirect class instead
+     * @see LookupRef\Indirect::INDIRECT()
+     *      Use the INDIRECT() method in the LookupRef\Indirect class instead
      *
      * NOTE - INDIRECT() does not yet support the optional a1 parameter introduced in Excel 2010
      *
@@ -192,8 +192,6 @@ class LookupRef
      * @param Cell $pCell The current cell (containing this formula)
      *
      * @return array|string An array containing a cell or range of cells, or a string on error
-     *
-     * @TODO    Support for the optional a1 parameter introduced in Excel 2010
      */
     public static function INDIRECT($cellAddress, Cell $pCell)
     {
@@ -212,7 +210,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the OFFSET() method in the LookupRef\Offset class instead
+     * @see LookupRef\Offset::OFFSET()
+     *      Use the OFFSET() method in the LookupRef\Offset class instead
      *
      * @param null|string $cellAddress The reference from which you want to base the offset.
      *                                     Reference must refer to a cell or range of adjacent cells;
@@ -248,31 +247,16 @@ class LookupRef
      * Excel Function:
      *        =CHOOSE(index_num, value1, [value2], ...)
      *
+     * @Deprecated 1.18.0
+     *
+     * @see LookupRef\Selection::choose()
+     *      Use the choose() method in the LookupRef\Selection class instead
+     *
      * @return mixed The selected value
      */
     public static function CHOOSE(...$chooseArgs)
     {
-        $chosenEntry = Functions::flattenArray(array_shift($chooseArgs));
-        $entryCount = count($chooseArgs) - 1;
-
-        if (is_array($chosenEntry)) {
-            $chosenEntry = array_shift($chosenEntry);
-        }
-        if ((is_numeric($chosenEntry)) && (!is_bool($chosenEntry))) {
-            --$chosenEntry;
-        } else {
-            return Functions::VALUE();
-        }
-        $chosenEntry = floor($chosenEntry);
-        if (($chosenEntry < 0) || ($chosenEntry > $entryCount)) {
-            return Functions::VALUE();
-        }
-
-        if (is_array($chooseArgs[$chosenEntry])) {
-            return Functions::flattenArray($chooseArgs[$chosenEntry]);
-        }
-
-        return $chooseArgs[$chosenEntry];
+        return LookupRef\Selection::choose(...$chooseArgs);
     }
 
     /**
@@ -285,7 +269,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the MATCH() method in the LookupRef\ExcelMatch class instead
+     * @see LookupRef\ExcelMatch::MATCH()
+     *      Use the MATCH() method in the LookupRef\ExcelMatch class instead
      *
      * @param mixed $lookupValue The value that you want to match in lookup_array
      * @param mixed $lookupArray The range of cells being searched
@@ -309,7 +294,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the index() method in the LookupRef\Matrix class instead
+     * @see LookupRef\Matrix::index()
+     *      Use the index() method in the LookupRef\Matrix class instead
      *
      * @param mixed $rowNum The row in the array or range from which to return a value.
      *                          If row_num is omitted, column_num is required.
@@ -329,7 +315,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the transpose() method in the LookupRef\Matrix class instead
+     * @see LookupRef\Matrix::transpose()
+     *      Use the transpose() method in the LookupRef\Matrix class instead
      *
      * @param array $matrixData A matrix of values
      *
@@ -350,7 +337,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the lookup() method in the LookupRef\VLookup class instead
+     * @see LookupRef\VLookup::lookup()
+     *      Use the lookup() method in the LookupRef\VLookup class instead
      *
      * @param mixed $lookup_value The value that you want to match in lookup_array
      * @param mixed $lookup_array The range of cells being searched
@@ -372,7 +360,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the lookup() method in the LookupRef\HLookup class instead
+     * @see LookupRef\HLookup::lookup()
+     *      Use the lookup() method in the LookupRef\HLookup class instead
      *
      * @param mixed $lookup_value The value that you want to match in lookup_array
      * @param mixed $lookup_array The range of cells being searched
@@ -393,7 +382,8 @@ class LookupRef
      *
      * @Deprecated 1.18.0
      *
-     * @see Use the lookup() method in the LookupRef\Lookup class instead
+     * @see LookupRef\Lookup::lookup()
+     *      Use the lookup() method in the LookupRef\Lookup class instead
      *
      * @param mixed $lookup_value The value that you want to match in lookup_array
      * @param mixed $lookup_vector The range of cells being searched
@@ -409,6 +399,11 @@ class LookupRef
     /**
      * FORMULATEXT.
      *
+     * @Deprecated 1.18.0
+     *
+     * @see LookupRef\Formula::text()
+     *      Use the text() method in the LookupRef\Formula class instead
+     *
      * @param mixed $cellReference The cell to check
      * @param Cell $pCell The current cell (containing this formula)
      *
@@ -416,22 +411,6 @@ class LookupRef
      */
     public static function FORMULATEXT($cellReference = '', ?Cell $pCell = null)
     {
-        if ($pCell === null) {
-            return Functions::REF();
-        }
-
-        preg_match('/^' . Calculation::CALCULATION_REGEXP_CELLREF . '$/i', $cellReference, $matches);
-
-        $cellReference = $matches[6] . $matches[7];
-        $worksheetName = trim($matches[3], "'");
-        $worksheet = (!empty($worksheetName))
-            ? $pCell->getWorksheet()->getParent()->getSheetByName($worksheetName)
-            : $pCell->getWorksheet();
-
-        if (!$worksheet->getCell($cellReference)->isFormula()) {
-            return Functions::NA();
-        }
-
-        return $worksheet->getCell($cellReference)->getValue();
+        return LookupRef\Formula::text($cellReference, $pCell);
     }
 }
diff --git a/src/PhpSpreadsheet/Calculation/LookupRef/Formula.php b/src/PhpSpreadsheet/Calculation/LookupRef/Formula.php
new file mode 100644
index 00000000..d96b5040
--- /dev/null
+++ b/src/PhpSpreadsheet/Calculation/LookupRef/Formula.php
@@ -0,0 +1,43 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Calculation\LookupRef;
+
+use PhpOffice\PhpSpreadsheet\Calculation\Calculation;
+use PhpOffice\PhpSpreadsheet\Calculation\Functions;
+use PhpOffice\PhpSpreadsheet\Cell\Cell;
+
+class Formula
+{
+    /**
+     * FORMULATEXT.
+     *
+     * @param mixed $cellReference The cell to check
+     * @param Cell $pCell The current cell (containing this formula)
+     *
+     * @return string
+     */
+    public static function text($cellReference = '', ?Cell $pCell = null)
+    {
+        if ($pCell === null) {
+            return Functions::REF();
+        }
+
+        preg_match('/^' . Calculation::CALCULATION_REGEXP_CELLREF . '$/i', $cellReference, $matches);
+
+        $cellReference = $matches[6] . $matches[7];
+        $worksheetName = trim($matches[3], "'");
+        $worksheet = (!empty($worksheetName))
+            ? $pCell->getWorksheet()->getParent()->getSheetByName($worksheetName)
+            : $pCell->getWorksheet();
+
+        if (
+            $worksheet === null ||
+            !$worksheet->cellExists($cellReference) ||
+            !$worksheet->getCell($cellReference)->isFormula()
+        ) {
+            return Functions::NA();
+        }
+
+        return $worksheet->getCell($cellReference)->getValue();
+    }
+}
diff --git a/src/PhpSpreadsheet/Calculation/LookupRef/Hyperlink.php b/src/PhpSpreadsheet/Calculation/LookupRef/Hyperlink.php
new file mode 100644
index 00000000..d0324964
--- /dev/null
+++ b/src/PhpSpreadsheet/Calculation/LookupRef/Hyperlink.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Calculation\LookupRef;
+
+use PhpOffice\PhpSpreadsheet\Calculation\Functions;
+use PhpOffice\PhpSpreadsheet\Cell\Cell;
+
+class Hyperlink
+{
+    /**
+     * HYPERLINK.
+     *
+     * Excel Function:
+     *        =HYPERLINK(linkURL,displayName)
+     *
+     * @param mixed $linkURL Expect string. Value to check, is also the value returned when no error
+     * @param mixed $displayName Expect string. Value to return when testValue is an error condition
+     * @param Cell $pCell The cell to set the hyperlink in
+     *
+     * @return mixed The value of $displayName (or $linkURL if $displayName was blank)
+     */
+    public static function set($linkURL = '', $displayName = null, ?Cell $pCell = null)
+    {
+        $linkURL = ($linkURL === null) ? '' : Functions::flattenSingleValue($linkURL);
+        $displayName = ($displayName === null) ? '' : Functions::flattenSingleValue($displayName);
+
+        if ((!is_object($pCell)) || (trim($linkURL) == '')) {
+            return Functions::REF();
+        }
+
+        if ((is_object($displayName)) || trim($displayName) == '') {
+            $displayName = $linkURL;
+        }
+
+        $pCell->getHyperlink()->setUrl($linkURL);
+        $pCell->getHyperlink()->setTooltip($displayName);
+
+        return $displayName;
+    }
+}
diff --git a/src/PhpSpreadsheet/Calculation/LookupRef/Selection.php b/src/PhpSpreadsheet/Calculation/LookupRef/Selection.php
new file mode 100644
index 00000000..6c18d73b
--- /dev/null
+++ b/src/PhpSpreadsheet/Calculation/LookupRef/Selection.php
@@ -0,0 +1,46 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Calculation\LookupRef;
+
+use PhpOffice\PhpSpreadsheet\Calculation\Functions;
+
+class Selection
+{
+    /**
+     * CHOOSE.
+     *
+     * Uses lookup_value to return a value from the list of value arguments.
+     * Use CHOOSE to select one of up to 254 values based on the lookup_value.
+     *
+     * Excel Function:
+     *        =CHOOSE(index_num, value1, [value2], ...)
+     *
+     * @param mixed ...$chooseArgs Data values
+     *
+     * @return mixed The selected value
+     */
+    public static function choose(...$chooseArgs)
+    {
+        $chosenEntry = Functions::flattenArray(array_shift($chooseArgs));
+        $entryCount = count($chooseArgs) - 1;
+
+        if (is_array($chosenEntry)) {
+            $chosenEntry = array_shift($chosenEntry);
+        }
+        if (is_numeric($chosenEntry)) {
+            --$chosenEntry;
+        } else {
+            return Functions::VALUE();
+        }
+        $chosenEntry = floor($chosenEntry);
+        if (($chosenEntry < 0) || ($chosenEntry > $entryCount)) {
+            return Functions::VALUE();
+        }
+
+        if (is_array($chooseArgs[$chosenEntry])) {
+            return Functions::flattenArray($chooseArgs[$chosenEntry]);
+        }
+
+        return $chooseArgs[$chosenEntry];
+    }
+}
diff --git a/src/PhpSpreadsheet/Calculation/MathTrig.php b/src/PhpSpreadsheet/Calculation/MathTrig.php
index 8398ba13..fad381b3 100644
--- a/src/PhpSpreadsheet/Calculation/MathTrig.php
+++ b/src/PhpSpreadsheet/Calculation/MathTrig.php
@@ -2,6 +2,9 @@
 
 namespace PhpOffice\PhpSpreadsheet\Calculation;
 
+/**
+ * @deprecated 1.18.0
+ */
 class MathTrig
 {
     /**
diff --git a/tests/PhpSpreadsheetTests/Calculation/LookupRefTest.php b/tests/PhpSpreadsheetTests/Calculation/LookupRefTest.php
index af8b8079..9f4c90b3 100644
--- a/tests/PhpSpreadsheetTests/Calculation/LookupRefTest.php
+++ b/tests/PhpSpreadsheetTests/Calculation/LookupRefTest.php
@@ -41,6 +41,8 @@ class LookupRefTest extends TestCase
             $remoteSheet = $this->getMockBuilder(Worksheet::class)
                 ->disableOriginalConstructor()
                 ->getMock();
+            $remoteSheet->method('cellExists')
+                ->willReturn(true);
             $remoteSheet->method('getCell')
                 ->willReturn($remoteCell);
 
@@ -53,6 +55,8 @@ class LookupRefTest extends TestCase
             $sheet = $this->getMockBuilder(Worksheet::class)
                 ->disableOriginalConstructor()
                 ->getMock();
+            $sheet->method('cellExists')
+                ->willReturn(true);
             $sheet->method('getCell')
                 ->willReturn($remoteCell);
             $sheet->method('getParent')