Uncaught Reference Error : jQuery is not defined

This is a test module to explore passing a variable from php to Javascript.

jsm2.js

(function ($) {
  Drupal.behaviors.jsm2 = {
    attach: function (context, settings) {     
      alert(Drupal.settings.jsm2.vat_rate); 
    }
  };
}(jQuery));

jsm2.module

<?php
drupal_add_js(array('jsm2' => array('vat_rate' => '0.2')), 'setting');
?>

jsm2.info

name = jsm2
description = Javascript Expt 4
core = 7.x
scripts[] = jsm2.js

When the module is installed the console shows this message:  Uncaught Reference Error : jQuery is not defined at drupal.js ?p9aoin:5

Can anyone help with suggesting what I might be doing wrong ?  Thanks.

Drupal version: 


Source: https://www.drupal.org/taxonomy/term/4/feed