Automate calculation of percentages based on date range for dashboard

[Excel__N00B]

I am hoping to create a dashboard for use in undertaking spot checks of work undertaken by members of my department.

Data will be entered into a spreadsheet in the format of:

[TABLE="width: 500"]
<tbody>[TR]
[TD]ID
[/TD]
[TD]Date
[/TD]
[TD]Status
[/TD]
[/TR]
[TR]
[TD]1
[/TD]
[TD]Jan 2015
[/TD]
[TD]Green
[/TD]
[/TR]
[TR]
[TD]2
[/TD]
[TD]Jan 2015
[/TD]
[TD]Green
[/TD]
[/TR]
[TR]
[TD]3
[/TD]
[TD]Jan 2015
[/TD]
[TD]Green
[/TD]
[/TR]
[TR]
[TD]4
[/TD]
[TD]Feb 2015
[/TD]
[TD]Amber
[/TD]
[/TR]
[TR]
[TD]5
[/TD]
[TD]Feb 2015
[/TD]
[TD]Red
[/TD]
[/TR]
[TR]
[TD]6
[/TD]
[TD]Mar 2015
[/TD]
[TD]Amber
[/TD]
[/TR]
</tbody>[/TABLE]

I would like for there to be a dashboard where the user can select a date range. A chart will then be generated which has the percentage of green, amber and red ratings for the months within the date range.

This is where I am struggling to find a solution. The data is simple to record in the spreadsheet. However, I would like the user to be able to select a date range on the dashboard which then calculates the percentages for each month, e.g. Jan 2015 = 100% Green, 0% Amber and 0% Red. This is then used to populate a chart.

A static solution will not work as data will be continuously added. I have been struggling with terminology so my searching of Google has not turned up a great deal. I am thinking pivot tables may be of some use but thought I would check here before wasting hours.

Thanks.