text:  This is Marketplace. I'm Kimberly Adams. There are other entities actually planning to go dark in the coming days. Tomorrow, the Federal Reserve will enter one of its so-called blackout or quiet periods through the first of August. These periods are generally around 10 days before a federal open market committee meeting and one day after when policymakers and staff with the Fed can't talk about macroeconomic issues or monetary policy with members of the public.