GDP = C + I + G + (x - m)

Where:
- **C** = Consumer spending
- **I** = Investments (business capital spending)
- **G** = Government spending
- **x** = Exports
- **m** = Imports

GDP is a country income, ignore business to business activity 



Source:
In the US the Bureau of economic analysis (BEA) publishes an avanced release of quartely GDP **4 weeks after the quarter end**.
And a final release **3 month after the quarter end**
The BEA headline represent real GDP levels and real GDP growth. 
Nominal GDP is also included in the BEA report under the name "current dollard"