I took some measurements using a couple of meters I have.
Samsung Charger with Samsung Cable:
9.12V * 1.595A = 14.546 watts
Power Delivery (Google Pixel 2 XL Charger and Cable):
8.39V * 1.93A = 16.19 watts
I also tested with different cables that I already verified that were good and a couple of different chargers for Power Delivery and Quick Charge and results were similar to the measurements above.