1diff --git a/DOCS.md b/DOCS.md
  2index 88a439e..9635e49 100644
  3--- a/DOCS.md
  4+++ b/DOCS.md
  5@@ -1860,6 +1860,16 @@
  6 @returns {number} 
  7 @constructor
  8 ```
  9+
 10+### COVAR 
 11+
 12+```
 13+  Returns the covariance of the product of paired deviations. 
 14+@param dataY - The first range of data. 
 15+@param dataX - The second range of data. 
 16+@returns {number} 
 17+@constructor
 18+```
 19 ## Text
 20 
 21 
 22diff --git a/TODO.md b/TODO.md
 23index 91e8cfb..85bd4be 100644
 24--- a/TODO.md
 25+++ b/TODO.md
 26@@ -54,7 +54,6 @@ For example 64 tbs to a qt.
 27 * TO_DOLLARS - Contingent upon cells having display formats derived from type-hierarchy
 28 * TO_PERCENT - Contingent upon cells having display formats derived from type-hierarchy
 29 * TO_TEXT - Contingent upon cells having display formats derived from type-hierarchy
 30-* COVAR
 31 * CRITBINOM
 32 * F.DIST.RT
 33 * HYPGEOMDIST
 34diff --git a/dist/Formulas/AllFormulas.js b/dist/Formulas/AllFormulas.js
 35index 6a837e8..fd2811d 100644
 36--- a/dist/Formulas/AllFormulas.js
 37+++ b/dist/Formulas/AllFormulas.js
 38@@ -170,6 +170,7 @@ exports.GEOMEAN = Statistical_1.GEOMEAN;
 39 exports.HARMEAN = Statistical_1.HARMEAN;
 40 exports.CONFIDENCE = Statistical_1.CONFIDENCE;
 41 exports.BINOMDIST = Statistical_1.BINOMDIST;
 42+exports.COVAR = Statistical_1.COVAR;
 43 var Text_1 = require("./Text");
 44 exports.ARABIC = Text_1.ARABIC;
 45 exports.CHAR = Text_1.CHAR;
 46diff --git a/dist/Formulas/Statistical.js b/dist/Formulas/Statistical.js
 47index 137bd06..c064564 100644
 48--- a/dist/Formulas/Statistical.js
 49+++ b/dist/Formulas/Statistical.js
 50@@ -1477,3 +1477,27 @@ var BINOMDIST = function (successes, trials, probability, cumulative) {
 51     return (cumulative) ? _binomialCDF(successes, trials, probability) : _binomialPDF(successes, trials, probability);
 52 };
 53 exports.BINOMDIST = BINOMDIST;
 54+/**
 55+ * Returns the covariance of the product of paired deviations.
 56+ * @param dataY - The first range of data.
 57+ * @param dataX - The second range of data.
 58+ * @returns {number}
 59+ * @constructor
 60+ */
 61+var COVAR = function (dataY, dataX) {
 62+    ArgsChecker_1.ArgsChecker.checkLength(arguments, 2, "COVAR");
 63+    dataY = Filter_1.Filter.flattenAndThrow(dataY).map(TypeConverter_1.TypeConverter.valueToNumber);
 64+    dataX = Filter_1.Filter.flattenAndThrow(dataX).map(TypeConverter_1.TypeConverter.valueToNumber);
 65+    if (dataX.length !== dataY.length) {
 66+        throw new Errors_1.NAError("COVAR has mismatched argument count " + dataY.length + " vs " + dataX.length + ".");
 67+    }
 68+    var mean1 = MathHelpers_1.mean(dataY);
 69+    var mean2 = MathHelpers_1.mean(dataX);
 70+    var result = 0;
 71+    var n = dataY.length;
 72+    for (var i = 0; i < n; i++) {
 73+        result += (dataY[i] - mean1) * (dataX[i] - mean2);
 74+    }
 75+    return result / n;
 76+};
 77+exports.COVAR = COVAR;
 78diff --git a/src/Formulas/AllFormulas.ts b/src/Formulas/AllFormulas.ts
 79index c30dc27..8e342d7 100644
 80--- a/src/Formulas/AllFormulas.ts
 81+++ b/src/Formulas/AllFormulas.ts
 82@@ -175,7 +175,8 @@ import {
 83   GEOMEAN,
 84   HARMEAN,
 85   CONFIDENCE,
 86-  BINOMDIST
 87+  BINOMDIST,
 88+  COVAR
 89 } from "./Statistical";
 90 import {
 91   ARABIC,
 92@@ -422,5 +423,6 @@ export {
 93   N,
 94   UNARY_PERCENT,
 95   MULTINOMIAL,
 96-  BINOMDIST
 97+  BINOMDIST,
 98+  COVAR
 99 }
100\ No newline at end of file
101diff --git a/src/Formulas/Statistical.ts b/src/Formulas/Statistical.ts
102index 24d1d79..1592b64 100644
103--- a/src/Formulas/Statistical.ts
104+++ b/src/Formulas/Statistical.ts
105@@ -1473,6 +1473,31 @@ var BINOMDIST = function (successes, trials, probability, cumulative) {
106 };
107 
108 
109+/**
110+ * Returns the covariance of the product of paired deviations.
111+ * @param dataY - The first range of data.
112+ * @param dataX - The second range of data.
113+ * @returns {number}
114+ * @constructor
115+ */
116+var COVAR = function (dataY, dataX) {
117+  ArgsChecker.checkLength(arguments, 2, "COVAR");
118+  dataY = Filter.flattenAndThrow(dataY).map(TypeConverter.valueToNumber);
119+  dataX = Filter.flattenAndThrow(dataX).map(TypeConverter.valueToNumber);
120+  if (dataX.length !== dataY.length) {
121+    throw new NAError("COVAR has mismatched argument count " + dataY.length + " vs " + dataX.length + ".");
122+  }
123+  var mean1 = mean(dataY);
124+  var mean2 = mean(dataX);
125+  var result = 0;
126+  var n = dataY.length;
127+  for (var i = 0; i < n; i++) {
128+    result += (dataY[i] - mean1) * (dataX[i] - mean2);
129+  }
130+  return result / n;
131+};
132+
133+
134 export {
135   AVERAGE,
136   AVERAGEA,
137@@ -1518,5 +1543,6 @@ export {
138   GEOMEAN,
139   HARMEAN,
140   CONFIDENCE,
141-  BINOMDIST
142+  BINOMDIST,
143+  COVAR
144 }
145\ No newline at end of file
146diff --git a/tests/Formulas/StatisticalTest.ts b/tests/Formulas/StatisticalTest.ts
147index b1ae495..ce85a03 100644
148--- a/tests/Formulas/StatisticalTest.ts
149+++ b/tests/Formulas/StatisticalTest.ts
150@@ -43,7 +43,8 @@ import {
151   GEOMEAN,
152   HARMEAN,
153   CONFIDENCE,
154-  BINOMDIST
155+  BINOMDIST,
156+  COVAR
157 } from "../../src/Formulas/Statistical";
158 import * as ERRORS from "../../src/Errors";
159 import {
160@@ -915,4 +916,18 @@ test("BINOMDIST", function() {
161   catchAndAssertEquals(function() {
162     BINOMDIST.apply(this, [20, 20, 1, true, 10]);
163   }, ERRORS.NA_ERROR);
164+});
165+
166+test("COVAR", function() {
167+  assertEquals(COVAR([2, 4, 5, 1, 3], [7, 3, 1, 3, 4]), -1.5999999999999999);
168+  assertEquals(COVAR([2, 4, 5, 1], [7, 3, 1, 3]), -2);
169+  catchAndAssertEquals(function() {
170+    COVAR([2, 4, 5, 1], [7, 3, 1, 3, 4]);
171+  }, ERRORS.NA_ERROR);
172+  catchAndAssertEquals(function() {
173+    COVAR.apply(this, [[10, 10, 10]]);
174+  }, ERRORS.NA_ERROR);
175+  catchAndAssertEquals(function() {
176+    COVAR.apply(this, [[10, 10, 10], [1, 2, 4], 1000000]);
177+  }, ERRORS.NA_ERROR);
178 });
179\ No newline at end of file
180diff --git a/tests/SheetFormulaTest.ts b/tests/SheetFormulaTest.ts
181index 5bd5766..f23e273 100644
182--- a/tests/SheetFormulaTest.ts
183+++ b/tests/SheetFormulaTest.ts
184@@ -821,6 +821,14 @@ test("Sheet MULTINOMIAL", function(){
185   assertFormulaEquals('=MULTINOMIAL(2, 22)', 276);
186 });
187 
188+test("Sheet BINOMDIST", function(){
189+  assertFormulaEquals('=BINOMDIST(14, 22, 0.4, true)', 0.9929516025629364);
190+});
191+
192+test("Sheet COVAR", function(){
193+  assertFormulaEquals('=COVAR([2, 4, 5, 1], [7, 3, 1, 3])', -2);
194+});
195+
196 test("Sheet *", function(){
197   assertFormulaEquals('= 10 * 10', 100);
198   assertFormulaEquals('= 10 * 0', 0);