Die Mär vom Ersparnis­überhang der Reichen als Ursache der säku­laren Stagnation

Am kommenden Sonntag spreche ich mit Professor Thomas Mayer über ein breites Themenspektrum. Ausgangspunkt ist die These der “säkularen Stagnation” – immer wieder als Argument bzw. Entschuldigung für die Geldpolitik angeführt. So auch von Martin Wolf, der sich auf eine neue Studie beruft (die ich auch mit Prof. Mayer diskutiere):

  • “A paper by Atif Mian, Ludwig Straub and Amir Sufi (…) reaches a conclusion (that) the principal explanation for the decline in real interest rates has been high and rising inequality and not demographic factors, such as the savings behaviour of the ‘baby-boom’ generation over their lifetimes, as some have argued.” – bto: Es liegt also nicht an der Abhängigkeitsquote, sondern daran, dass die Reichen mehr sparen und deshalb zu wenig nachfragen. So zumindest die Studie.
  • “The analysis starts with estimates of the real ‘natural rate’ of interest, a concept that goes back to the Swedish economist Knut Wicksell. The natural rate, he explained, balances demand and supply in the economy, which shows itself in stable prices. (…) estimates of this rate for the US show a fall from about 4 per cent four decades ago to around zero now.” – bto: Der Rückgang des Zinssatzes ist ein wichtiger Treiber für den Anstieg der Vermögenspreise.
  • “(…) the decline ‘raises concerns about secular stagnation, threatens asset price bubbles, and complicates monetary polic’. Indeed, it is a big part of the reason why central banks have had to make huge asset purchases in crisis situations, such as now.” – bto: Das Modell ist klar: Weil die Reichen so viel sparen, müssen die Zinsen sinken und daraufhin steigen die Vermögenspreise, die wiederum nicht fallen dürfen, damit die Realwirtschaft keinen Schaden nimmt.
  • “Their main point is that savings rates vary far more by income within age cohorts than they do across age cohorts. The differences are also huge: in the US, the top 10 per cent of households by income have a savings rate between 10 and 20 percentage points higher than the bottom 90 per cent. Given this divergence, the shift in the distribution of income towards the top inevitably raised the overall propensity to save. As an explanation of rising propensities to save and the falling real interest rate, the shift of the baby-boom generation into middle age does not work, because rising savings have been continuous while the impact of the demographic shift on savings behaviour has not.” – bto: Damit wird die Demografiethese widerlegt und eine Verteilungsthese eingeführt.
  • “At the aggregate level, savings must match investment. So what happens when the rich get richer and so try to save more? Interest rates must fall. It turns out that the impact of this on business investment is quite feeble. Indeed, the propensity to invest has been chronically weak, partly for demographic reasons.” – bto: Ich finde es witzig, dass man so ein Modell verwendet, wo wir doch wissen, dass es keiner Ersparnisse bedarf, um Investitionen zu finanzieren. Die Banken schaffen das Geld im Kreditvergabeakt.
  • “So the offsets have had to come either from persistent fiscal deficits or from higher spending by the bottom 90 per cent. Both are fuelled by debt, while the latter is also powered by asset price bubbles, especially in house prices.” – bto: Schulden müssen steigen und Vermögenspreise erhöhen die Ungleichheit weiter. Verstanden.
  • As central banks pursue the natural rate downwards, they drive both of these processes. But, as debt ratios rise, natural rates fall still further, as the highly indebted become ever less creditworthy.” – bto: So, jetzt sinkt die Konsistenz der Argumentation. Denn hier wird gesagt, die Notenbanken müssen die Zinsen senken, damit die Schuldner keine Probleme bekommen.
  • “There is no powerful reason to expect income inequality, the fundamental driver of today’s excess savings, to reverse, although it might stabilise. There is an excellent reason for a huge investment boom, notably the climate transition. But that will not occur without consistent, determined, intelligent and globally aware policymaking, none of which we can expect, though we may hope. So, in the medium to long term, secular stagnation is likely to return, unless income inequality falls.” – bto: Man kann aber auch sagen, dass die Geldpolitik diese Ungleichheit erst geschaffen hat. Es wird eine Gegenbewegung geben.
  • “The short term is harder to read (…). The surge in inflation has in fact surprised almost everybody. The worry must be that the price shocks persist and then get baked into expectations, which will then only be reversed by a period of significantly higher short-term rates. That would cause stagflation, which would create painful dilemmas for central banks and surely cause devastating problems for weaker borrowers, notably but not exclusively heavily indebted emerging economies.” – bto: Das wiederum ist interessant. Wolf schließt eine Inflationsspirale nicht aus.
  • The exceptional policies of 2020 can no longer be justified. (…) We have more than enough money today and bond yields ought to rise a little. When the facts change, central banks should change their minds. That time is now.” – bto: Das ist undenkbar, denn das halten Vermögensmärkte und Schuldner nicht aus.

ft.com (Anmeldung erforderlich): „Inequality is behind central bank dilemma”, 21. September 2021