created customer value

Business/Marketing/CustomerValue.php

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+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   phpOMS\Business\Marketing
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace phpOMS\Business\Marketing;
+
+use phpOMS\Math\Matrix\IdentityMatrix;
+use phpOMS\Math\Matrix\Matrix;
+use phpOMS\Math\Matrix\Vector;
+
+/**
+ * Marketing CustomerValue
+ *
+ * @package phpOMS\Business\Marketing
+ * @license OMS License 1.0
+ * @link    https://orange-management.org
+ * @since   1.0.0
+ */
+final class CustomerValue
+{
+    /**
+     * Simple customer lifetime value
+     *
+     * @param float $margin        Margin per period
+     * @param float $retentionRate Rate of remaining customers per period
+     * @param float $discountRate  Cost of capital to discound future revenue
+     *
+     * @return float
+     *
+     * @since 1.0.0
+     */
+    public static function getSimpleCLV(float $margin, float $retentionRate, float $discountRate) : float
+    {
+        return $margin * $retentionRate / (1 + $discountRate - $retentionRate);
+    }
+
+    /**
+     * Normalized measure of recurring revenue
+     *
+     * @param array $revenues Revenues
+     * @param int   $periods  Amount of revenue periods
+     * @param float $cutoff   Normalization cutoff (which values should be ignored)
+     *
+     * @return float
+     *
+     * @since 1.0.0
+     */
+    public static function getMRR(array $revenues, int $periods = 12, float $cutoff = 0.1) : float
+    {
+        if ($cutoff === 0.0) {
+            return \array_sum($revenues) / $periods;
+        }
+
+        $count  = \count($revenues);
+        $offset = (int) \round($count * $cutoff, 0, \PHP_ROUND_HALF_UP);
+
+        if ($offset * 2 >= $count) {
+            return 0.0;
+        }
+
+        \sort($revenues);
+        $normalized = \array_splice($revenues, $offset, $count - $offset);
+
+        return \array_sum($normalized) / $periods;
+    }
+}