yeah that's fair, without wholesale rack prices as a baseline you can't really isolate station behaviour from what's happening upstream.
>without wholesale rack prices as a baseline
The US government publishes data on this (eg. https://www.eia.gov/petroleum/gasdiesel/). The UK government might have something similar. Barring that, you can use Brent crude as a proxy.
>without wholesale rack prices as a baseline
The US government publishes data on this (eg. https://www.eia.gov/petroleum/gasdiesel/). The UK government might have something similar. Barring that, you can use Brent crude as a proxy.