Prikazi in analize/Discussion Papers Growth-at-Risk and Financial Stability: Concept and Application for Slovenia Marija Drenkovska, Robert Volčjak July 2022 Zbirka/ Collection: Prikazi in analize/Discussion papers Naslov/ Title: Growth-at-Risk and Financial Stability: Concept and Application for Slovenia Številka/ No.: 5 Leto/ Year: 2022 Izdajatelj/ Published by: Banka Slovenije Slovenska 35, 1505 Ljubljana, Slovenija www.bsi.si Elektronska izdaja/ Electronic edition: https:/ www.bsi.si/publikacije/raziskave-in-analize/prikazi-in-analize Mnenja in zaključki, objavljeni v prispevkih v tej publikaciji, ne odražajo nujno uradnih stališč Banke Slovenije ali njenih organov. Uporaba in objava podatkov ter delov besedila sta dovoljeni le z navedbo vira. The views and conclusions expressed in the papers in this publication do not necessarily reflect the official position of Banka Slovenije or its bodies. The figures and text herein may only be used or published if the source is cited. © Banka Slovenije Kataložni zapis o publikaciji (CIP) pripravili v Narodni in univerzitetni knjižnici v Ljubljani COBISS.SI-ID 130038531 ISBN 978-961-6960-72-4 (PDF) Growth-at-Risk and Financial Stability: Concept and Application for Slovenia∗ Marija Drenkovska† Robert Volčjak‡ Abstract This paper explores the information that measures of increased vulnerabilities and cyclical systemic risk in the financial system contain about the downside risk in the real economy. The connection between macrofinancial conditions and economic activity in this paper is assessed using the growth-at-risk (GaR) approach on Slovenian macrofinancial data. We show that the prevailing financial conditions influence the tail risks regardless of the time horizon, and the medium horizon risks are more dependent upon systemic financial vulnerabilities, such as when credit growth is excessive. These results have significant potential to inform macroprudential policy, the conduct of which implies managing risks for real economic activity stemming from financial imbalances in a forward-looking manner. Keywords: growth-at-risk, macroprudential policy, systemic risk, financial conditions, financial stability, probability distribution JEL Classification: E44, E47, E58, E66. ∗The views presented herein are those of the author and do not necessarily represent the official views of Banka Slovenije or of the Eurosystem. We would like to thank Changchun Wang for his assistance and useful comments on the coding issues related to the LDA. †Banka Slovenije, Financial Stability and Macroprudential Policy, author’s email account: mar- ija.drenkovska@bsi.si ‡Banka Slovenije, Financial Stability and Macroprudential Policy, author’s email account: robert.volcjak@bsi.si Povzetek Analiza obravnava informacije, ki jih vsebujejo merila povečane ranljivosti in cikli- čnega sistemskega tveganja v finančnem sistemu o tveganju padca aktivnosti real-nega sektorja gospodarstva. Povezava med makrofinančnimi pogoji in gospodarsko aktivnostjo je v prispevku ocenjena z uporabo metode tvegane rasti (growth-at-risk) na slovenskih makrofinančnih podatkih. Prikazano je, da prevladujoče finančne razmere vplivajo na repna tveganja ne glede na časovno obdobje ter da so srednjeročna tveganja bolj odvisna od sistemskih finančnih ranljivosti, kot je to na primer prekomerna rast kreditov. Z dobljenimi rezultati se lahko zelo obogati informacijska baza za makrobonitetno politiko, ki vključuje v prihodnost usmerjeno obvladovanje tveganj, ki izhajajo iz finančnih neravnovesij, za realno gospodarsko aktivnost. 1 Interaction between the financial system and real activity (tail-growth) The experiences of the global financial crisis have reignited the academic and policy debate on the relationship between the imbalances of the financial sector and the severe downturns in the real economy. At the heart of this debate was the realization that financial stability has a critical bearing on macroeconomic outcomes (Blanchard et al., 2010). Theoretical studies have already confirmed that the evolution of macrofinancial vulnerabilities carries important signals about evolving risks to future economic activity. There are two main causes of tail events i.e. severe downturns with a low probability of occurrence, such as the 2008 global financial crisis. One is carried in the information that is embedded in the state of the financial conditions prior to the crisis, while the other is the systemic risk that is reflected in the position in the credit cycle. The link between financial structure (i.e. credit cycles) and macroeconomic activity has been long established in the literature.1 In times when the economy is expanding and investment opportunities appear ample and easy to finance, macro-financial vulnerabilities build up and consequently the risk of accelerated and prolonged effects of the potential shocks to the economy increases. In the case of such shock, financial imbalances – such as excessive leverage and overpriced assets – may result in unfavourable interactions between the financial system and the real economy. The built-up macrofinancial imbalances are often followed by severe recessions and financial crises.2 In that sense, economic growth responds non-linearly to adverse shocks, which can further lead to a significant reduction in financial stability and consequently amplify the adverse macroeconomic situation. The sources of the non-linear response of economic growth are the constraints that economic agents face when financing their activities, or so called financial frictions.3 These amplify the relationships (transmission mechanism) between the real economy and the financial system. This amplifying mechanism works through the ease of financing in upturns of the cycle when asset prices are high. At the same time the risk premia are low, as the volatility on the financial markets is also low. However, should a shock hit such a vulnerable, highly leveraged economy, the asset prices would be among the first to strongly (and negatively) react to it, where even small changes 1Gertler (1988) in his work thoroughly surveys the early works and discussion on this macrofinancial link, while Bernanke (1993) has extensively discussed the macroeconomic role of the credit aggregates. 2See, for example, Kaminsky and Reinhart (1999), Claessens et al. (2011), Gourinchas and Obstfeld (2012), Schularick and Taylor (2012), and Mian et al. (2017). 3Works that incorporate models in which financial intermediaries face financial constraints in the financial sector include, among others Gertler and Kiyotaki (2010) and Gertler and Karadi (2011). 1 can lead to major equity losses. As pointed out by Deutsche Bundesbank (2021),4 the initial shock may be amplified in a non-linear way by a self-reinforcing interaction between asset prices and financial and market liquidity frictions in the economy. Experience and empirical evidence support the view that financial vulnerabilities increase risks to growth and that recessions accompanied by financial crises are typically much more severe and protracted than ordinary recessions.5 The powerful feedback effect between financial imbalances and the real economy has also been corroborated by Nalban and Sm˘ adu (2022) who show that “when financial uncertainty shocks hit the economy, the effects are significantly larger, with output responding about ten times stronger compared to both productivity and preference uncertainty shocks of a comparable magnitude.” In the context of the financial market’s agents, the asymmetric response of the real economy can also be observed in its recovery after a financial shock. While a downturn is, as Minsky (1975) noted, triggered by a collapse in confidence of either borrowers or lenders, the beginning of an upturn is conditioned by the solid confidence of both sides, which experience has shown to be restored in a slow and cautious manner. The financial and economic crisis of 2008-09 revealed the need for a re-examination of the financial regulation and brought forward a renewed focus on macroprudential policy, which aims to address systemic risk, that is, “the risk of developments that threaten the stability of the financial system as a whole and consequently the broader economy” (Bernanke, 2009. In times of expansion the decisions made by market players may certainly make sense at the micro level, but they more often than not neglect the potential negative implications for the stability of the financial system as a whole. In the context of the financial stability, macroprudential policy is mandated to prevent and reduce the accumulation of systemic risks by strengthening the resilience of the financial system. That is to say, the policies of macroprudential authorities must be designed in such a way as to counteract the build-up of financial vulnerabilities, which is expected to eventually lead to reduced downside risks in the real economy. Although managing economic growth is not the direct objective of macroprudential policy, an absence of financial stability manifests itself in a higher likelihood of deep recessions. In this regard, there has been a growing need in the past years for the development of a quantitative framework for macroprudential policy assessment and design. Past attempts to do this have faced several challenges. From one side, there are a variety of tools – including many that are still in developmental phases – which face problems with either data limitations or the relatively short historical experience with their use. Yet another set of challenges reflects the non-integrated way the separate 4Please see their report for a more detailed discussion on the amplification mechanism. 5See for example, Claessens et al. (2011a, 2011b) 2 risk assessment tools have been used in informing macroprudential policy decisions. Additionally, certain challenges may be also identified in the vaguely defined concepts and measures of systemic risk and vulnerabilities that are used in this concept. An important line of thinking proposes the use of macroprudential policy to manage real GDP growth distribution, in particular downside risks.6 The following sections offers a short conceptual background of growth-at-risk (GaR) and an overview of the relevant work based on the GaR approach. Section 3 sets out the methodological approach used in the estimation of the GaR for Slovenia and Section 4 presents the results of the analysis. Section 5 discusses the usefulness of the GaR tool as an important part of a wider framework that can provide substantial information to macroprudential authorities in managing the risks to real economic activity that arise from financial imbalances in a forward-looking manner. Section 6 concludes and sets the stage for further work. 2 Growth-at-risk – conceptual background The concept of growth-at-risk has received an increased attention in recent years from assessments of impact of systemic risk on economic output growth, to identifying macroprudential policy options for managing tail risk. The term itself was first used by Wang and Yao (2001), who proposed an assessment of financial systemic risk by extending the idea of value-at-risk, a popular risk management concept. The growth-at-risk concept and methods were later popularized by the seminal paper of Adrian et al. (2019a)7 and the subsequent generation of growth-at-risk models and applications. In this literature, and by analogy with value-at-risk (VaR), the growth-at-risk (GaR) corresponds to the probability that future real GDP growth will fall below a prede-termined threshold. In statistical terminology, the GaR of an economy over a given horizon is a certain chosen low quantile of the distribution of the (projected) GDP growth rate over such a horizon. Unlike the standard macroeconomic forecasting practices, where the focus is usually on the expected value of GDP growth, the GaR approach takes into account the overall distribution of the growth. By focusing on the low quantiles of future growth (a conventional practice in risk management) the GaR measure provides a foundation for assessing the severity of potential adverse outcomes and their implications. Additional to this measure, and perhaps more important from a macroprudential authority 6See for example Brandao-Marques et al. (2020), Carney (2020), Duprey and Ueberfeldt (2020), Galán (2020), Cechetti and Suarez (2020), and Suarez (2020). 7Throughout this paper, the work of Adrian et al. (2019a) is interchangeably referenced as Adrian et al. (2016) as it was originally published as a Federal Reserve Bank of New York Staff Report, before being published by the American Economic Review in 2019. 3 perspective, the GaR approach can provide information on the variables that deter-mine the probability or severity of bad outcomes, including policy variables that may then be used to address such aggregate risk. It provides an assessment of their relative importance, which, expectedly, varies along the probabilistic distribution of growth and according to the forecast horizon. Earlier works based on the GaR approach introduce a new macroeconomic measure of financial stability by linking financial conditions (Adrian et al., 2016; IMF, 2017), financial gap (Bank of Japan, 2018) or asset price booms (Ceccheti, 2008) to the probability distribution of future GDP growth. These studies point to strong variation of the lower quantiles of the distribution of future GDP growth, while the upper quantiles remain stable over time. Subsequent research based on GaR models introduces the credit aggregates as an additional measure and assesses the impact of credit cycle risks on future growth distribution (Aikman et al., 2018; Aikman et al., 2019; Duprey et al., 2018a; Duprey et al., 2018b; Duprey and Ueberfeldt, 2018; Galan, 2020). Some of these works already place the focus on operationalization of the growth-at-risk approach and incorporating it into a holistic macroprudential policy framework. The works of Duprey and Ueberfeldt (2018) and Galan (2020) emphasise the feasibility of the GaR approach in evaluating the effects of macroprudential policies on low probability tail events. Finally, there is the current ongoing work at national authorities level and at the ESRB (2021) Expert Group on Macroprudential Stance, whose aim is to offer operational methods for assessing the macroprudential stance. They see the macroprudential policy as “a risk management approach to safeguarding financial stability, in which policymakers assess the level of systemic risk compatible with financial stability and adjust their policies accordingly to achieve a neutral stance.” The GaR approach is one of the several in the toolkit they propose for regular monitoring and providing input in broader policy deliberations. The stance metric proposed in the related report and obtained by the GaR approach provides quantification of the future impacts from current vulnerabilities and conditions of the financial system by focusing on the downside risks to growth distribution. The current analysis follows the methodology proposed by Adrian et al. (2016) and the IMF (2017), and benefits greatly from the work done by the ESRB (2021) regarding the inclusion of additional measures and setting the GaR approach in a holistic macroprudential policy framework, which is currently under development at Banka Slovenije. 4 3 Estimating growth-at-risk for Slovenia – theoretical and empirical background Growth-at-risk is measured as a pre-defined quantile at the lower end of the distribution of the growth rate of a real economic variable of choice. In the related literature, the quantile of the chosen variable that corresponds with a tail risk is usually set at 5% or 10% of its distribution. The tail risk is thus estimated conditionally on selected explanatory variables, and for quarterly estimation procedures the real GDP is usually the key metric for economic activity, as financial crises manifest themselves in large GDP losses. 3.1 The quantile regression approach The estimation of the GaR is based on the estimation of a quantile regression, which is used to capture the effects of the explanatory variables on the forecasted GDP growth distribution. The concept of “quantile regression” has been developed by Koenker and Bassett (1978) and widely used in the GaR literature for identifying the effects of cyclical vulnerabilities and financial conditions on the tail risk of real economic growth.8 The quantile regression seeks to assess how much would a change in a conditioning variable in a multivariate regression affect the shape of the lower or upper tail of the distribution of the dependent variable. In terms of quantiles, the quantile regression tells us what happens to the τ th quantile of the distribution of Yt when the kth conditioning variable X(k) changes. t As opposed to linear regressions, the quantile regression can be used for estimating severe adverse outcomes in the tails of the real economic variable growth distribution, which can help us in the assessment of the transmission of financial conditions to the real economy. In contrast to linear regression, the quantile regression coefficients are estimated by linear programming. More specifically, the conditional quantiles of a dependent variable in a quantile regression are expressed as a linear function of the explanatory variables. In order to arrive at the estimation of the quantiles in the quantile regression, let us first look at the way a quantile can be found using linear programming. The τ th quantile of a discrete variable X is any number qτ such that Pr(Y < qτ ) ≤ τ ≤ Pr(Y ≥ qτ ). It can be shown that ˆ qτ is the solution to the following optimization problem,9 8See, for example, inter alia Cecchetti and Li (2008) and Adrian et al. (2019a.) 9The relation between a given quantile (τ ) and a selected explanatory variable impact on y occurs through a minimization process of the sum of absolute residuals (compared to the sum of squares in multiple regression). Positive residuals are given a weight of τ and negative residuals a weight of (1–τ ). The problem here is postulated as a non-linear optimization problem, but by reformulating the absolute values in a linear fashion we can arrive at a linear optimization problem. 5 presented in equation (1): ( ) 1 X X arg min τ |yt − q| + (1 − τ ) |yt − q| (1) q∈R T yt≥q yt