Here comes the Beige Book ...
The survey of contacts across the Fed's 12 districts will include anecdotes on the US economy and has been prepared ahead of the policy meeting in May.
Although none of its findings will count as concrete data, it could provide some insight into why so-called hard data on economic activity has recently slowed down.
"Clearly the updated performances on overall economic activity, inflation, hiring/wage performances will be of interest," wrote Sam Bullard, a senior economist at Wells Fargo, in a preview.
"Additionally, any comments businesses have regarding the lack of traction had thus far on the Trump agenda (and therefore frustrations, reduced optimism, reduced capex/hiring activity, etc…) will also be instructive to investors."
Ahead of the release of the Beige Book, traders saw a 41.8% chance that the Fed would raise rates at its meeting in June, according to Bloomberg's World Interest Rates Probability.