I have two days of teaching left in Helsinki and my next stop on Friday is Dublin where I will be discussing unification and exit. Should be a fun topic. Its Wednesday back home already and today I consider a matter that came up in one of my classes that I am taking in macroeconomics at the moment at the University of Helsinki. Students really struggle when first introduced to the idea of a stock and a flow. They can easily be led into defining a flow as a stock. Getting this absolutely right is one of the key building blocks in understanding basic macroeconomics and the links between the expenditure system and financial accumulation. Modern Monetary Theory (MMT) builds heavily on the difference between stocks and flows and is also what we call stock-flow consistent. So all flows that inform stocks are accounted for in a consistent way. So, for example, we know that when households save, which is the residual of disposable income that is not consumed and a flow, this accumulates into a stock of financial wealth. Today, I am seeking to clarify the issue in my class that we did not have sufficient time to deal with in detail last week. And after that, some music to restore sanity.