Get amount of time a WI has been in a given state? (javascript)

https://jazz.net/forum/questions/180890/defect-age-by-state

Not sure if anyone has done this yet, but the problem that I'm encountering is that the current time doesn't refresh when the page gets refreshed. 

I've used  both getTime() and Date.now() and it is the same thing. The date only gets refreshed when you change the state of the WI instead of automatically every time you refresh the page.

You can see this when you run a simple customized attribute with the following javascript

dojo.provide("com.example.GetTurnAroundTime");
dojo.require("com.ibm.team.workitem.api.common.WorkItemAttributes");
dojo.require("dojo.date");
dojo.require("dojo.date.stamp");

(function() {
    dojo.declare("com.example.GetTurnAroundTime", null, {
    getValue: function(attribute, workItem, configuration) {
        try {
           var WorkItemAttributes= com.ibm.team.workitem.api.common.WorkItemAttributes;
           var currentDate= Date.now(); 
  
           if(currentDate != null)
           return currentDate.toString();
        }
    }

  });
})();  

The end goal is to calculate how long the WI has been under a certain state, but this is the first step in solving this problem.

Any help or input would be appreciated.