Wiktionary
trade down
vb. 1 (context finance English) To lose value on the stock exchange. 2 To sell something and replace it with something cheaper.
Usage examples of "trade down".
For a time Blackbeard worked at his trade down on the Spanish Main, gathering, in the few years he was there, a very neat little fortune in the booty captured from sundry vessels.
It was rumoured he also had connections to the slave trade down in Kesh, and smugglers down in the southern islands.