Most people encounter the dollar sign on a daily basis: in stores, on websites, in the media and more. The symbol also serves as shorthand, referring to money, wealth, capitalism, commercialism ...

That’s benefiting the company, but it could be a warning sign for the wider economy. Dollar General said Tuesday that sales at stores open for at least a year had increased 2.4% last quarter.

Dollar stores, a bellwether for that group’s spending, started seeing signs of belt-tightening from their core consumers earlier this year. That trend has only continued into the latest quarter ...