Neither sentence fragment is correct.
To express the amount of trade, you might say, "the level of trade". Or you might say, "the price at which <good> is being traded"
For example:
"The level of trade in the United States has dropped due to taxes on imported goods."
"The level of trade in Europe was affected by Britain leaving the European Union."
"The price at which oil is being traded has dropped due to increases in renewable energy sources."
"The price wheat is being traded at is affected by government subsidies."