after the global financial crisis were without precedent. this meant that macroprudential policies had to be implemented and calibrated with great uncertainty as to their actual effects. now that many policies have been put in place and initial experiences have been gained, we are in a position to evaluate and thus improve our understanding of their effects. policy evaluation provides information on whether policies achieve their objectives or whether unintended consequences materialise. policy evaluation, however, is not a trivial task as it needs to answer three key questions : 1. did the reform “ cause ” an outcome ( attribution )? 2. did the reform have similar effects across relevant markets, states of the world, or jurisdictions and regions ( heterogeneity )? 3. did the reform achieve its overall objective ( aggregation / general equilibrium )? these questions cannot be answered by taking a purely national perspective. recent work at the financial stability board ( fsb ) is a good example of how internationally coordinated evaluation has become part of the policy process : in 2017, during the german g20 presidency, the fsb developed a framework to evaluate the effects of the g20 post - crisis reforms of financial regulation ( financial stability board 2017 ). the fsb subsequently launched several evaluation projects. three projects have already been completed or are close to being finished : 2 the first project provided evidence that post - crisis reforms generated incentives to centrally clear otc derivatives. the second project showed no material negative effects of reforms on infrastructure financing. the third project analyses reform effects on the availability of funding for small and mediumsized enterprises. the recently - published consultation report showed no persistent negative effects of the g20 regulatory reforms on sme financing overall. ongoing evaluation work at the fsb deals with one of the g20 ’ s core objective – reducing the systemic and moral hazard risks associated with systemically important financial institutions. 3 a first evaluation plan has been published on the fsb ’ s website. 4 workshops will be held with stakeholders from academia, the financial sector, and representatives of civil society. the too - big - to - fail ( tbtf ) evaluation will address three main questions : 1. were the reforms effective in reducing the perceived probability of the impact of failure of systemically important institutions? this question can be addressed by assessing changes in estimates of implicit funding subsidies and analysing progress in the resolvability of systemically important banks. 2. are reforms resulting in altered bank behaviour in terms of changes in funding structures,

from a financial stability angle, two factors are crucial in this respect : developments over time, and the risk level. low interest rates might fuel demand for mortgage loans, which might give rise to a selfreinforcing interaction between lending and prices. however, the results of a bundesbank survey of banks have indicated that the risks inherent in real estate business are hardly procyclical. all in all, mortgage loans grew at no more than a modest pace – at 2 % per year, to be precise – while lending standards have hardly been loosened. what we do see, though, are signs of structural vulnerability within the german banking system. the surveys found that 100 % financing arrangements are certainly no longer out of the ordinary in the surveyed towns and cities. if a decline in urban real estate prices were to coincide with climbing default rates, this would have a considerable impact on banks ’ profits. a scenario like this might well be manageable, were it to occur in isolation. but experience has taught us that real estate crises normally go hand in hand with a downturn in the broader economy. if this occurred simultaneously, it could prove to be very trying indeed for banks. besides continuing to monitor developments in the real estate market, we currently see two areas in which action is needed. first, we are laying the groundwork for closing major data gaps. second, we are evaluating what fundamental legislation is needed to even more effectively counter risk in the real estate market going forward. 6. banking union and financial stability we have taken a huge step forward at the european level this year. the european single supervisory mechanism can apply a consistent and strict standard of supervision and compare banks across national borders, meaning that risks to financial stability can be identified earlier on. while it is true that it is primarily the nation states which decide on the use of macroprudential instruments, the european central bank, too, has been given macroprudential powers, and it can tighten national regulations. that makes sense and averts the danger of not addressing risks to financial system stability in good time. but the banking union also provides answers to another key question : who is to bear risks that have materialised? in the pre - crisis era, there were no effective procedures for dealing with major banks that had run into difficulties. all too often, the cost of risks that materialised were passed on to the taxpayer, while private sector owners and creditors were hardly ever made liable. looking ahead, the single resolution mechanism, the