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Depending on your company custom calendar needs, a new type of calendar fields may be available to view as created by a dashboard designer.
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New Analytics Functions
As an a viewer now you can drill down to a widget to gain better understanding of data. Here is an article to help you get started with it - : Drill into a widget example
Monitoring your key KPIs by getting alerts using Pulse. To enable Pulse and alerts, here is an article that will help you: Pulse. You will not be able to create a pulse alert as a Viewer, however you will be able to receive alerts as configured by a Designer
To learn more how about Forecasting algorithms Models: Click Here