Classes
@cfg {String} tz The timezone for analysis in the form like America/New_York
@cfg {String} [validFromField = "ValidFrom"]
@cfg {String} [validToField = "ValidTo"]
@cfg {String} [uniqueIDField = "ObjectID"]
@cfg {String} granularity 'month', 'week', 'quarter', etc. Use Time.MONTH, Time.WEEK, etc.
@cfg {Number} numberOfPeriodsToShow
@cfg {String[]} [fieldsToSum=[]] It will track the count automatically but it can keep a running sum of other fields also