Power BI is a great investment for any ERP company which has a considerable amount of data, it allows you to dig into the various modules in your system, link them all together and extract meaningful information from raw data. 

With the release of Dynamics GP 2018, Microsoft has introduced Power BI - Content Pack for Dynamics GP which includes the following:
  • Financial 
  • Purchasing
  • Sales
  • Inventory
The power BI pack can be downloaded from the following link.  Although, it is important to take into consideration that you will be prompted to provide the Odata link in order to connect the power BI to Dynamics GP and start retrieving data. Refer to Microsoft Article on OData
Here is the Power BI Content Pack
Power BI Content Pack

Best Regards, 
Mahmoud M. AlSaadi