diff --git a/src/isShorthandProperty.js b/src/isShorthandProperty.js
index 4389f3d..3321cc0 100644
--- a/src/isShorthandProperty.js
+++ b/src/isShorthandProperty.js
@@ -6,5 +6,5 @@ const shortHandProperties = require('./formatted-data/shorthand-properties.json'
  * @returns {boolean} - true if property is a shorthand, false otherwise
  */
 module.exports = function isShorthandProperty(property) {
-  return Object.keys(shortHandProperties).includes(property);
+  return shortHandProperties[property] != undefined;
 };