1diff --git a/src/RawFormulas/Date.ts b/src/RawFormulas/Date.ts
  2index 834e583..8f4fa71 100644
  3--- a/src/RawFormulas/Date.ts
  4+++ b/src/RawFormulas/Date.ts
  5@@ -3,6 +3,7 @@ import * as moment from "moment";
  6 import * as Formula from "formulajs"
  7 import {
  8   ArgsChecker,
  9+  DateRegExBuilder,
 10   TypeCaster
 11 } from "./Utils";
 12 import {
 13@@ -138,7 +139,17 @@ var DATEVALUE = function (...values) : number {
 14   // Check YYYY/MM/DD
 15   if (m === undefined) {
 16     // For reference: https://regex101.com/r/uusfi7/5
 17-    var matches = dateString.match(/^\s*(([0-9][0-9][0-9][0-9])|([1-9][0-9][0-9]))\/([1-9]|0[1-9]|1[0-2])\/([1-9]|[0-2][0-9]|3[0-1])\s*$/);
 18+    var REG = /^\s*(([0-9][0-9][0-9][0-9])|([1-9][0-9][0-9]))\/([1-9]|0[1-9]|1[0-2])\/([1-9]|[0-2][0-9]|3[0-1])\s*$/;
 19+    REG = DateRegExBuilder.DateRegExBuilder()
 20+      .start()
 21+      .YYYY()
 22+      .SLASH_DELIMITOR()
 23+      .MM()
 24+      .SLASH_DELIMITOR()
 25+      .DD()
 26+      .end()
 27+      .build();
 28+    var matches = dateString.match(REG);
 29     if (matches && matches.length === 6) {
 30       var years = parseInt(matches[1]);
 31       var months = parseInt(matches[4]) - 1; // Months are zero indexed.
 32diff --git a/src/RawFormulas/Utils.ts b/src/RawFormulas/Utils.ts
 33index 975f2c6..d0fdd86 100644
 34--- a/src/RawFormulas/Utils.ts
 35+++ b/src/RawFormulas/Utils.ts
 36@@ -364,9 +364,97 @@ class Serializer {
 37 }
 38 
 39 
 40+/**
 41+ * Build a regular expression step by step, to make it easier to build and read the resulting regular expressions.
 42+ */
 43+class DateRegExBuilder {
 44+  private regexString = "";
 45+  private static ZERO_OR_MORE_SPACES = "\\s*";
 46+  private static ONE_OR_MORE_SPACES = "\\s+";
 47+
 48+  static DateRegExBuilder() : DateRegExBuilder {
 49+    return new DateRegExBuilder();
 50+  }
 51+
 52+  start() : DateRegExBuilder {
 53+    this.regexString += "^" + DateRegExBuilder.ZERO_OR_MORE_SPACES;
 54+    return this;
 55+  }
 56+
 57+  end() : DateRegExBuilder {
 58+    this.regexString += DateRegExBuilder.ZERO_OR_MORE_SPACES + "$";
 59+    return this;
 60+  }
 61+
 62+  /**
 63+   * Adds a match group for zero or more whitespace tokens.
 64+   * @returns {DateRegExBuilder}
 65+   */
 66+  zeroOrMoreSpaces() : DateRegExBuilder {
 67+    this.regexString += DateRegExBuilder.ZERO_OR_MORE_SPACES;
 68+    return this;
 69+  }
 70+
 71+  /**
 72+   * Adds a match group for zero or more whitespace tokens.
 73+   * @returns {DateRegExBuilder}
 74+   */
 75+  oneOrMoreSpaces() : DateRegExBuilder {
 76+    this.regexString += DateRegExBuilder.ONE_OR_MORE_SPACES;
 77+    return this;
 78+  }
 79+
 80+  SLASH_DELIMITOR() : DateRegExBuilder {
 81+    this.regexString += "\\/";
 82+    return this;
 83+  }
 84+
 85+  /**
 86+   * Adds all month full name and short names to the regular expression.
 87+   * @returns {DateRegExBuilder}
 88+   */
 89+  monthNameCaptureGroup() : DateRegExBuilder {
 90+    this.regexString += "(january|february|march|april|may|june|july|august|september|october|november|december|jan|feb|mar|apr|jun|jul|aug|sep|oct|nov|dec)";
 91+    return this;
 92+  }
 93+
 94+  /**
 95+   * Adds month digit to the regular expression.
 96+   * @returns {DateRegExBuilder}
 97+   */
 98+  MM() : DateRegExBuilder {
 99+    this.regexString += "([1-9]|0[1-9]|1[0-2])";
100+    return this;
101+  }
102+
103+  /**
104+   *
105+   * @returns {DateRegExBuilder}
106+   */
107+  DD() : DateRegExBuilder {
108+    this.regexString += "([1-9]|[0-2][0-9]|3[0-1])";
109+    return this;
110+  }
111+
112+  YYYY() : DateRegExBuilder {
113+    this.regexString += "(([0-9][0-9][0-9][0-9])|([1-9][0-9][0-9]))";
114+    return this;
115+  }
116+
117+  /**
118+   * Builds the regular expression.
119+   * @returns {RegExp} Built up string as a regular expression.
120+   */
121+  build() : RegExp {
122+    return new RegExp(this.regexString);
123+  }
124+}
125+
126+
127 export {
128   ArgsChecker,
129   CriteriaFunctionFactory,
130+  DateRegExBuilder,
131   Filter,
132   Serializer,
133   TypeCaster