budget related query

Hi Team,

I’d like to understand how and from where the budget values are being generated in the Performance Max campaign type — particularly for objectives such as Website Trafficand others — in Google Ads. Could you please share the relevant API references (e.g., gRPC or REST)and explain how these budget values are being calculated?

As shown in the attached screenshot, I’d like to know the source and logic behind these numbers.

Thank you.