This study employs synthetic control methods to estimate the effect of the Iberian exception mechanism on wholesale electricity prices and consumer inflation, for both Spain and Portugal. We find that the intervention led to an average reduction of approximately 40% in the spot price of electricity between July 2022 and June 2023 in both Spain and Portugal. Regarding overall inflation, we observe notable differences between the two countries. In Spain, the intervention has an immediate effect, and results in an average decrease of 3.5 percentage points over the twelve months under consideration. In Portugal, however, the impact is small and generally close to zero. Different electricity market structures in each country are a plausible explanation.

We study how deposit competition affects a bank's decision to securitize mortgages. Exploiting the state-specific removal of deposit market caps across the U.S. as a source of competition, we find a 7.1 percentage point increase in the probability that banks securitize mortgage loans. This result is driven by an 11 basis point increase in deposit costs and corresponding reductions in banks' deposit holdings. Our results are strongest among banks that rely more on deposit funding. These findings highlight a hitherto undocumented and unintended regulatory cause that motivates banks to adopt the originate-to-distribute model.

On September 25th, financial economists from all over the world travelled for the 11th time to Halle (Saale) to attend the annual FIN-FIRE Workshop at IWH. During two days, authors of ten papers covered a comprehensive overview of contemporary issues that pose potential challenges to the financial system, including data privacy in mortgage markets, climate risks in bond markets, synthetic risk transfers, the effects of geopolitical risks for lending, as well as granular perspectives on the transmission of monetary policy. An intense exchange of thoughts between authors, discussants, and the audience yielded genuinely new insights into the resilience and fragility of financial systems. 

Das Klimaschutzgesetz (KSG) sieht eine Reduktion der deutschen Treibhausgasemissionen bis zum Jahr 2030 um 65% gegenüber den Emissionen im Jahr 1990 vor. Der Ausstieg aus der thermischen Verwertung der Kohle (vor allem der Braunkohle) leistet einen substanziellen Beitrag zum Erreichen dieser Ziele. Der Kohleausstieg stellt die Braunkohlereviere (und die Standorte der Steinkohlekraftwerke) jedoch vor strukturpolitische Herausforderungen. Um den Strukturwandel in diesen Regionen aktiv zu gestalten, hat der Bundestag im August 2020 mit Zustimmung des Bundesrats das Strukturstärkungsgesetz Kohleregionen (StStG) beschlossen. Über dieses Gesetz stellt der Bund bis zum Jahr 2038 Finanzhilfen in Höhe von 41,09 Mrd. Euro zur Verfügung. Im Fokus der Politikmaßnahmen stehen verschiedene Ziele, vor allem gesamtwirtschaftliche (Wertschöpfung, Wachstum, Steueraufkommen), wettbewerbliche (Produktivität), arbeitsmarktpolitische (Beschäftigung, Beschäftigungsstrukturen), verteilungspolitische (regionale Disparitäten) sowie klimapolitische (Treibhausgasreduzierung, Nachhaltigkeit). 

Die im StStG vorgesehenen strukturpolitischen Interventionen umfassen ein breites Maßnahmenbündel. Das Gesetz fordert eine begleitende wissenschaftliche Evaluierung des Gesetzes. Bei dem vorliegenden Bericht handelt es sich um das dritte Dokument in diesem Evaluierungszyklus. Der erste Bericht (Brachert u.a., 2023) präsentierte ein erstes Lagebild nach dem Start der im Rahmen des Investitionsgesetzes Kohleregionen (InvKG) und des STARK-Bundesprogramms geplanten Maßnahmen. Der zweite Bericht (Brachert u.a., 2025) enthielt eine Aktualisierung und erweiterte Aussagen zu den möglichen Effekten der Maßnahmen aus dem InvKG. An diesem Punkt setzt der vorliegende Zwischenbericht 2025 an. Es gehen immer mehr Maßnahmen in die Umsetzung, wodurch der Strukturwandel an Fahrt aufnimmt. Jedoch bleibt auch für diesen Bericht zu berücksichtigen, dass viele der geplanten Maßnahmen noch nicht oder gerade erst begonnen haben, was bei einer fast zwanzigjährigen Laufzeit des Programms naheliegend ist. Die in diesem Bericht vorgelegten empirischen Analysen basieren auf dem Datenstand vom 31.12.2024, also rund viereinhalb Jahre nachdem das InvKG in Kraft getreten ist.

Zwischenbericht 2025 zur begleitenden Evaluierung des Investitionsgesetzes Kohleregionen (InvKG) und des STARK-Bundesprogramms 

Am 5. November 2025 wurde der Zwischenbericht 2025 zur begleitenden Evaluierung des Investitionsgesetzes Kohleregionen (InvKG) und des STARK‑Bundesprogramms von den Wirtschaftsforschungsinstituten IWH und RWI veröffentlicht. Die Evaluierung, die im Auftrag des Bundesministeriums für Wirtschaft und Energie durchgeführt wird, analysiert die Fortschritte der Programme, identifiziert die Wirkungen der Förderung und gibt konkrete Handlungsempfehlungen, wie die Maßnahmen optimiert werden können, um die Transformation der vom Kohleausstieg betroffenen Regionen in Deutschland erfolgreich zu gestalten.

We exploit staggered real estate transaction tax (RETT) hikes across German states to identify the effect of house price changes on mortgage credit supply. Based on approximately 33 million real estate online listings, we construct a quarterly hedonic house price index (HPI) between 2008:q1 and 2017:q4, which we instrument with state-specific RETT changes to isolate the effect on mortgage credit supply by all local German banks. First, a RETT hike by one percentage point reduces HPI by 1.2%. This effect is driven by listings in rural regions. Second, a 1% contraction of HPI induced by an increase in the RETT leads to a 1.4% decline in mortgage lending. This transmission of fiscal policy to mortgage credit supply is effective across almost the entire bank capitalization distribution.

We examine how banks manage carbon transition risk by selling loans given to polluting borrowers to less regulated shadow banks in securitization markets. Exploiting the election of Donald Trump as an exogenous shock that reduces carbon risk, we find that banks’ securitization decisions are sensitive to borrowers’ carbon footprints. Banks are more likely to securitize brown loans when carbon risk is high but swiftly change to keep these loans on their balance sheets when carbon risk is reduced after Trump’s election. Importantly, securitization enables banks to offer lower interest rates to polluting borrowers but does not affect the supply of green loans. Our findings are more pronounced among domestic banks and banks that do not display green lending preferences. We discuss how securitization can weaken the effectiveness of bank climate policies through reducing banks’ incentives to price carbon risk.

The economic transformation is visibly reshaping the world of work. At the Halle Institute for Economic Research (IWH), the Structural Change and Productivity Department will intensify its analysis of these developments – and is evolving in the process. A high-profile conference with an unusual format recently provided important momentum.

DThe interactions between supply chains and sustainable finance have become a key area of research in financial markets, driven by growing global awareness of environmental and social challenges. Article 1 examines how lenders use sustainability clauses to monitor borrowers with negative environmental incidents and compares the use of this unique loan agreement design with conventional loan terms, financial and balance sheet-related clauses. We show that lenders are less inclined to include sustainability clauses in the loan agreement if a borrower has a history of negative environmental incidents. In contrast, lenders use sustainability clauses to attract institutional investors to participate in syndication rather than as monitoring tools for borrowers' environmental performance. Article 2 examines whether banks associated with biodiversity loss in the Amazon region experience a withdrawal of deposits when depositors become aware of their financing activities. I find empirical evidence that so-called ‘Amazon carbon banks’ experience slower growth in deposits once depositors learn about their financing activities. This effect is particularly pronounced when Amazon carbon banks have branches in counties that experience greater biodiversity loss compared to other branches. Article 3, how European companies that are heavily integrated into global supply chains (GSC) are affected by a supply chain disruption (Covid-19). We show that Covid-19 negatively affects the revenue growth of companies that are heavily dependent on GSC in their home country. Crucially, we uncover the role of banking relationships in mitigating the disruptive effects.

We study the corporate-loan pricing decisions of a major, systemic bank during the Greek financial crisis. A unique aspect of our data set is that we observe both the actual interest rate and the “break-even rate” (BE rate) of each loan, as computed by the bank’s own loan-pricing department (in effect, the loan’s marginal cost). We document that low-BE-rate (safer) borrowers are charged significant markups, whereas high-BE-rate (riskier) borrowers are charged smaller and even negative markups. We rationalize this de facto cross-subsidization through the lens of a dynamic model featuring depressed collateral values, impaired capital-market access, and limit pricing.