Thanks for the post @Diqing Wu ,
AFAIK, the graph you are referencing is powered by the Azure Cost Management service which has the native ability to visualize and analyze usage cost data using one/many of the supported dimensions/attributes including resource type, resource groups etc.
If you haven't already, I recommend watching this 8 min tutorial on Grouping and filtering options in Cost Analysis.
Also recommend checking out this section of the FAQ for additional guidance.
For more questions, raise a billing support request to engage the right billing experts to provide additional guidance.
Hope this helps but don't hesitate to ping if you have any follow-up questions.