Countdown Values return 0
<p>I have to set a countdown to the 15th of every month.  I'm able to successfully get the difference value needed to countdown to the 15th.</p>

<p>After calculating the difference, I calculate the days, hours, min, secs.  </p>

<p>Everything else besides days returns a value of 0</p>

<pre><code>export default React.createClass({
  tick: function() {
    var currentDate = new Date();
    var date_till_15 = new Date();

    if (currentDate.getDate() &lt; 15) {
      var days_till_15 = 15 - currentDate.getDate();
      date_till_15 = new Date(date_till_15.setDate(currentDate.getDate() + days_till_15 ));
    } else if(currentDate.getDate() &gt; 15){
      date_till_15 = new Date(date_till_15.setMonth(currentDate.getMonth() + 1));
      date_till_15 = new Date(date_till_15.setDate(15));
    }

    var difference =  date_till_15 - currentDate;
    var daysLeft = 0, hoursLeft = 0, minutesLeft = 0, secondsLeft = 0;

    if (difference &gt; 0) {
      daysLeft = Math.floor( difference / (1000*60*60*24) );
      difference -= daysLeft * (1000*60*60*24);
      hoursLeft = Math.floor( difference / (1000*60*60) );
      difference -= hoursLeft * (1000*60*60);
      minutesLeft = Math.floor( difference / (1000*60) );
      difference -= minutesLeft * (1000*60);
      secondsLeft = Math.floor( difference/1000 );

      this.setState({
        days: daysLeft,
        hours: hoursLeft,
        minutes: minutesLeft,
        seconds: secondsLeft
      });
    }   else {
      clearInterval( this.timeInterval );
      this.setState({ expired: true });
    }
  },

  componentDidMount: function(){
    this.timeInterval = setInterval( this.tick.bind(this), 1000);
  },

  render() { 
    return (
      &lt;div&gt;
        {this.state &amp;&amp;
          &lt;div&gt;
            &lt;div&gt;{this.state.days}&lt;/div&gt;
            &lt;div&gt;{this.state.minutes}&lt;/div&gt;
          &lt;/div&gt;
        }
      &lt;/div&gt;
    )
  }
});
</code></pre>