If you read the report it states that “The real change in private inventories added 0.16 percentage point to the third-quarter change in real GDP …”
So, the inventory increase that you are citing added 0.16 to the GDP.
So, let’s discount the 0.16% due to inventory increase and we get a GDP revised upward to better than 2%% from 1.6%. Still not great, but better than previously thought.
So the invenotries contributed, but over 70% of the revision upwards came from other factors. What are these factors ?