Submitted:
04 February 2026
Posted:
06 February 2026
You are already at the latest version
Abstract
Keywords:
1. Introduction
- Are private investors necessary to secure the future of Germany’s educational infrastructure, and to what extent can investments in educational infrastructure be financially beneficial for private investors?
- Which socio-economic indicators moderate the investment backlog in educational real estate, and can they be used to identify high-need municipalities?
2. Literature Review
Fiscal Federalism and the Roots of Infrastructure
Public-Private Partnerships as a Financing Mechanism.
Educational Real Estate:
Impact Investing and ESG Alignment
3. Methods
Data and Sample Selection
- Investment Backlog: The reported total investment backlog for school infrastructure in a municipality (€). This figure, while based on municipal self-reporting and subject to variation in estimation methods, represents the best available proxy for the scale of need.
- Planned Investments: The total planned investments in school infrastructure for the period 2025-2028, as reported in municipal financial plans (€).
- Pupil Data: Total number of pupils, forecasts for 2033/34, and the distribution between public and private schools.
- Socio-Economic Indicators: Inhabitants, GDP per capita (2022), change in GDP per capita (2015–2022), and unemployment rates.
- Real Estate Indicators: Base rent for apartments and houses from leading real estate portals (Immoscout, Engel & Völkers), serving as a proxy for local market wealth and attractiveness.
- Municipal Finance: Data on municipal debt, reserves, and budget balances.
Methods of Analysis
4. Results
The Scale of the Investment Chasm: A Descriptive Overview
| Metric | Total Value (€) | Median per Municipality (€) |
|---|---|---|
| Total Estimated Investment Backlog | 9,974,400,000 | 1,224,000,000 |
| Total Planned Investments (2025-2028) | 9,139,129,594 | 226,511,500 |
Evaluating the Drivers of the Investment Backlog
| Hypothesis | Independent Variable | Dependent Variable | Expected Relationship |
Result | Supported? |
|---|---|---|---|---|---|
| H2 | GDP Growth (2015-2022) | Investment Backlog per Pupil | Negative | Weak Negative Correlation (r = -0.29) |
Partially |
| H3 | Rent Levels (€/m²) | Investment Backlog per Pupil | Negative | No Significant Correlation |
No |
| H4 | Pupil Growth Forecast | Investment Backlog | Positive | No Significant Correlation |
No |
| H5 | Investment Backlog per Pupil | Planned Investment per Pupil | Positive | Strong Positive Correlation (r = 0.86, p < 0.01) | Yes |
| H6 | Share of School Types | Investment Backlog | No Relationship | No Significant Relationship Found | Yes |
| H7 | Share of Private School Pupils | Investment Backlog | Negative | Significant Negative Correlation (r = -0.51, p < 0.05) | Yes |
- Economic Performance (H2 & H3): We expected that municipalities with weaker economic performance (lower GDP growth, lower rent levels) would have higher investment backlogs. However, the analysis revealed only a weak and not statistically significant negative correlation between GDP growth and the backlog per pupil (H2 partially supported). More strikingly, there was no significant correlation between local rent levels and the investment backlog (H3 not supported). This suggests that the backlog is a pervasive issue affecting both economically strong and weak cities, rather than being concentrated solely in fiscally distressed areas. Wealthier cities like Düsseldorf and Cologne have some of the largest backlogs in absolute terms.
- Demographic Pressure (H4): Contrary to expectations, there was no significant correlation between the projected increase in pupil numbers and the size of the investment backlog (H4 not supported). This indicates a potential disconnect in municipal planning, where future demographic needs are not yet systematically reflected in the assessment of current infrastructure deficits. The backlog is driven more by the legacy of past underinvestment than by initiative-taking planning for future growth.
- Planning Response (H5): A strong, statistically significant positive correlation was found between the investment backlog per pupil and the planned investment per pupil (H5 supported). This is an encouraging sign, suggesting that municipalities are, in principle, responsive to identified needs. Where the backlog is higher, planned spending is also higher. However, as established in H1, the magnitude of this response is insufficient to close the gap.
- Role of Private Schools (H7): A key finding emerged from testing H7. There is a statistically significant negative correlation between the share of pupils attending private schools and the public investment backlog (H7 supported). Municipalities with a higher proportion of students in the private system, such as Bonn and Münster, tend to have a lower public investment backlog. This provides strong empirical evidence that private schools can and do alleviate pressure on the public infrastructure system, corroborating the theoretical argument for their role in a diversified educational landscape.
Identifying High-Need Areas: The ‘Need Score’
| Rank | Municipality | Absolute ‘Need Score’ (€) |
|---|---|---|
| 1 | Cologne | 2,050,457,984 |
| 2 | Düsseldorf | 1,189,207,178 |
| 3 | Dortmund | 1,123,053,799 |
| 4 | Essen | 1,061,043,921 |
| 5 | Duisburg | 823,230,229 |
| 6 | Bonn | 763,553,248 |
| 7 | Wuppertal | 722,863,165 |
| 8 | Bochum | 620,832,238 |
| 9 | Bielefeld | 614,024,475 |
| 10 | Münster | 586,183,184 |
| 11 | Gelsenkirchen | 506,000,523 |
| 12 | Mönchengladbach | 473,088,294 |
| 13 | Aachen | 448,318,349 |
| 14 | Hagen | 385,827,872 |
| 15 | Krefeld | 363,225,511 |
| Rank | Municipality | Standardised ‘Need Score’ (€ per Inhabitant) |
|---|---|---|
| 1 | Bonn | 2,277 |
| 2 | Hagen | 2,057 |
| 3 | Wuppertal | 1,977 |
| 4 | Cologne | 1,878 |
| 5 | Essen | 1,826 |
| 6 | Münster | 1,840 |
| 7 | Düsseldorf | 1,906 |
| 8 | Gelsenkirchen | 1,974 |
| 9 | Dortmund | 1,911 |
| 10 | Bielefeld | 1,838 |
| 11 | Bochum | 1,709 |
| 12 | Aachen | 1,797 |
| 13 | Duisburg | 1,675 |
| 14 | Herne | 1,601 |
| 15 | Mönchengladbach | 1,833 |
Financial Feasibility for Private Investors
| Scenario | Rental Yield | Subsidy | IRR (Internal Rate of Return) | Equity Multiple |
|---|---|---|---|---|
| 1: Base Case | 4.5% | No | 5.9% | 2.5x |
| 2: Higher Yield | 5.5% | No | 7.8% | 3.3x |
| 3: Base with Subsidy | 4.5% | Yes (10%) | 7.9% | 3.1x |
| 4: Higher Yield with Subsidy | 5.5% | Yes (10%) | 10.3% | 4.1x |
| 5: Development Project | 6.5% | No | 19.8% | 5.2x |
5. Discussion
Policy Implications and Recommendations
Embrace Public-Private Partnerships as a Core Strategy
Streamline Bureaucracy and Strengthen Municipal Capacity
Use Public Funds Catalytically
For Private Investors: Seize the First-Mover Advantage
Adopt Composite Metrics for Investment Targeting
Incorporate Private Providers in School Development Planning
Limitations and Future Research
6. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
Appendix A
Detailed Variable List and Sources
Calculation of the ‘Need Score’
- R-squared: 0.751
- Adjusted R-squared: 0.722.
- F-statistic: 26.2 (p < 0.001)


References
- Andrade, E.; Padilla, L.; Carrington, S. J. Educational spaces: The relation between school infrastructure and learning outcomes. Heliyon 2024, 10(19), e38361. [Google Scholar] [CrossRef]
- Hampf, F.; Woessmann, L. Vocational vs. General Education and Employment over the Life Cycle: New Evidence from PIAAC. CESifo Economic Studies 2017, 63(3), 255–269. [Google Scholar] [CrossRef]
- Borghorst, M.; Brilon, S. Municipal investment backlog has reached a new high. KfW Kommunalpanel 2025. [Google Scholar]
- Hefetz, A.; Warner, M. Contracting or public delivery? The importance of service, market, and management characteristics. Journal of Public Administration Research and Theory 2012, 22(2), 289–317. [Google Scholar] [CrossRef]
- OECD. “PISA 2022 Results (Volume I and II) - Country Notes: Germany,” PISA 2022 Database, Tables I.B1.2.1, I.B1.2.2 and I.B1.2.3., 3 12 2023. Available online: https://www.oecd.org/en/about/programmes/pisa/pisa-publications.html (accessed on 3 5 2025).
- Barrett, P.; Davies, F.; Zhang, Y.; Barrett, L. The impact of classroom design on pupils’ learning: Final results of a holistic, multi-level analysis. Building and Environment 2015, 89, 118–133. [Google Scholar] [CrossRef]
- Kultusministerkonferenz, K. “Sekretariat der Kultusministerkonferenz,” Statistische Veröffentlichungen der Kultusministerkonferenz. 2024. [Google Scholar]
- Agrawal, D. R.; Brueckner, J. K.; Brülhart, M. Fiscal federalism in the twenty-first century. Annual Review of Economics 2024, 16(1), 429–454. [Google Scholar] [CrossRef]
- Fabre, A.; S. S. The Impact of Public–Private Partnerships (PPPs) in Infrastructure, Health, and Education. Journal of Economic Literature 2023, 61(2), 655–715. [Google Scholar] [CrossRef]
- Bremer, B.; Di Carlo, D.; Wansleben, L. The constrained politics of local public investment under cooperative federalism. Socio-Economic Review 2022, 21(2), 1007–1034. [Google Scholar] [CrossRef]
- Hodge, G. A.; Greve, C. Public–Private Partnerships: An International performance review. Public Administration Review 2007, 67(3), 545–558. [Google Scholar] [CrossRef]
- Ruming, K.; Liu, S. Universities as asset class: Private sector investment in property for universities. Geoforum 2024, 157, 104138. [Google Scholar] [CrossRef]
- Oates, W. E. An Essay on Fiscal Federalism. Journal of Economic Literature 1999, 37(3), 1120–1149. [Google Scholar] [CrossRef]
- Warner, M. E.; Hefetz, A. Insourcing and outsourcing. Journal of the American Planning Association 2012, 78(3), 313–327. [Google Scholar] [CrossRef]
- Auerbach, A. J. Tax Equivalences and Their Implications. Tax Policy and the Economy 2019, 33, 81–107. [Google Scholar] [CrossRef]
- Seitz, H. Fiscal Policy, Deficits and Politics of Subnational Governments: The Case of the German Laender. Public Choice 2000, 102, 183–218. [Google Scholar] [CrossRef]
- L. T.; W. S. Using public-private partnerships for the building and management of school assets and services. Engineering, Construction and Architectural Management 2014, 21(2), 206–223. [Google Scholar] [CrossRef]
- Kollatz-Ahnen, M.; Roick, M. J. Financing public sector investment. Public Sector Economics 2018, 42(2), 111–124. [Google Scholar] [CrossRef]
- De Mare, G.; Di Piazza, F. The Role of Public-Private Partnerships in School Building Projects. In in Computational Science and Its Applications; 2015. [Google Scholar]
- Hodge, G. A.; Greve, C. On Public–Private Partnership Performance: A Contemporary Review: A Contemporary Review. Public Works Management & Policy 2017, 22(1), 55–78. [Google Scholar]
- Scheller, H.; Walker, B. Municipal infrastructure policies in the Federal Republic—In between growing disparities and losing political autonomy? European Policy Analysis 2017, 3(2), 343–371. [Google Scholar] [CrossRef]
- Fleishman, L; Fogel, N; Fridman, I; S. Y. The effect of school performance on property values: a literature review and a case study. Journal of European Real Estate Research 2017, 10(3), 277–302. [Google Scholar] [CrossRef]
- Carlo, A.; Eichholtz, P. K. N. Three Decades of Global Institutional Investment in Real Estate. SSRN, 2021. [Google Scholar]
- Geltner, D. Real Estate Price Indices and Price Dynamics: An Overview from an Investments Perspective. Annual Review Financial Economics 2015, 7, 615–633. [Google Scholar] [CrossRef]
- Schrödl; Müller, K.; Cordes, E.; Lambertz, A. Der Markt für Schulimmobilien in Deutschland. In PwC Deutschland; 2025. [Google Scholar]
- Höchstädter, A.; Scheck, B. What’s in a Name: An Analysis of Impact Investing Understandings by Academics and Practitioners. J Bus Ethics 2015, 132, 449–475. [Google Scholar] [CrossRef]
- Monaghan, C.; King, E. How Theories of Change Can Improve Education Programming and Evaluation in Conflict-Affected Contexts. Comparative Education Review 2018, 62(3). [Google Scholar] [CrossRef]
- Moon, H.-C.; Parc, J.; Yim, S. H.; Park, N. An Extension of Porter and Kramer’s Creating Shared Value (CSV): Reorienting Strategies and Seeking International Cooperation. Journal of International and Area Studies 2011, 18(2), 49–64. [Google Scholar]

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2026 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).