Macroeconomists generally interpret the data they see as the unfolding of a Radner equilibrium, often with distortions, such as taxes, and with some incompleteness or dysfunction in the set of IOU markets.
This is from Kartik Athreya's Big Ideas in Macroeconomics, which is superb (and yes, he explains Radner equilibrium for the lay reader). I wish I'd had this book when I was preparing for PhD comprehensive exams, and in the future I will recommend it to anyone who wants to consume the writing of economists. I will say more about it later; it has much to absorb but I am nearly finished.
UPDATE: My full review of the book is here.