Government Debt Sustainability and Investments in Nigeria: Trends and Risk Thresholds amidst Macroeconomic Swings

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Kingsley Onyekachi Onyele
Eberechi Bernadine Ikwuagwu
Confidence Chinwe Opara


The core idea behind government debt is to fund fiscal deficit, which is anticipated to drive economic investments. To a larger extent, this is not the case, as evidenced in the Nigerian context, where debt has risen so high with investment levels declining, thus questioning the government's ability to manage and sustain its debt to pursue vital investment needs. This study aimed to investigate the threshold effect of debt sustainability on investments amidst macroeconomic swings from 1981 to 2020. In this regard, the threshold autoregressive regression (TAR) was used because it gave information on the optimal threshold of debt sustainability that would attract investments. Also, the Granger causality test was carried out to show the direction of causality among the variables. This paper concentrated on debt service to revenue and total debt stock to GDP as debt sustainability measures while investment was decomposed into public, private, and foreign investments. The paper yields that, based on the multivariate TAR analyses, the main threshold variables, that is, debt service to revenue and total debt stock to GDP, had a non-linear relationship with public, private, and foreign direct investments amidst changes in macroeconomic variables such as exchange rate, inflation, and monetary policy rate. The threshold coefficient of debt service to revenue indicated that public and foreign direct investments declined during low thresholds while private investment increased. However, the opposite prevailed when debt service to revenue exceeded the threshold values. However, the Granger causality test showed that debt service to revenue Granger caused total debt stock to GDP and exchange rate Granger caused debt service to revenue ratio, implying that exchange rate swings could affect the government's ability to service debt which in turn explains the non-linear relationship between debt sustainability and investments. Hence, it was concluded that Nigeria's lack of debt sustainability was associated with revenue generation, which explains why the models did not follow a linear path.


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Onyele, K. O., Ikwuagwu, E. B., & Opara, C. C. (2023). Government Debt Sustainability and Investments in Nigeria: Trends and Risk Thresholds amidst Macroeconomic Swings. PanAfrican Journal of Governance and Development (PJGD), 4(1), 18-52.
Research-based/ Original Articles
Author Biographies

Kingsley Onyekachi Onyele, Michael Okpara University of Agriculture, Nigeria

Kingsley O. Onyele holds a Ph.D. in Banking and Finance from the Michael Okpara University of Agriculture, Nigeria, specializing in International Finance, Trade, and Investment. He also holds a B.Sc. and an M.Sc. in Banking and Finance from Michael Okpara University of Agriculture, Nigeria. His research areas include international finance and investment, financial markets and institutions, public finance, econometrics, and corporate finance. He is currently a professional student member of the Institute of Chartered Accountants of Nigeria (ICAN).

Eberechi Bernadine Ikwuagwu, Michael Okpara University of Agriculture, Nigeria

Eberechi B. Ikwuagwu is a Lecturer at the Department of Banking and Finance, Michael Okpara University of Agriculture, Nigeria. She completed her Ph.D. with a specialization in International Finance and Investment from the Department of Banking and Finance, Enugu State University of Technology, Nigeria. She holds a B.Sc. and an M.Sc. in Banking and Finance from Michael Okpara University of Agriculture, Nigeria. Her major research areas are international finance and investment, banking, and corporate finance.

Confidence Chinwe Opara, Michael Okpara University of Agriculture, Nigeria

Confidence C. Opara did her B.Sc. and M.Sc. in Banking and Finance from Abia State University, Nigeria. She holds a Ph.D. in Banking and Finance from the Michael Okpara University of Agriculture, Nigeria, specializing in Financial Markets and Institutions. Her core research areas are financial markets and institutions, banking, corporate finance, econometrics, and public finance. She is a Lecturer at the Department of Banking and Finance, Michael Okpara University of Agriculture, Nigeria.


Abbas, A., & Christensen, J. (2010). The role of domestic debt markets in economic growth: An empirical investigation for low-income countries and emerging markets. Journal of Business Venturing, 19, 851-875.
Aderemi, T.O., Fagbola, L.O., Sokunbi. G.M., & Ebere, C.E. (2020). Investigating external debt and exchange rate fluctuations in Nigeria: any difference with ARDL model. Studia Universitatis Babeș-Bolyai Oeconomica, 65(3), 53-64. DOI: 10.2478/subboec-2020-0015
Aigheyisi, O.S. (2018). Oil price volatility and business cycles in Nigeria. Studies in Business and Economics, 13(2), 31-40.
Akinlo, A.E. (2021). Impact of external debt on economic growth: A Markov Regime- Switching Approach. Journal of Applied Financial Econometrics, 1(2), 123-143.
Al-Dughme, M.S. (2019). The impact of public debt and public investment on economic growth in Jordan. International Journal of Academic Research in Accounting, Finance and Management Sciences, 9(2), 149–157.
Aliu, A.S., Okeowo, I.A., Abosede, O.F., & Alabi, J.A. (2021). Debt burden and infrastructural development in Nigeria. International Journal Academic Research in Business and Social Sciences, 11(1), 419 – 432.
Anoke, B.I., Odo, S.I., & Nnabu, B.E. (2021). Public debt and domestic private investment: A crowding effect in Nigeria. International Journal of Research and Innovation in Social Science, 5(3), 1-8.
Bai, J., & Perron, P. (1998). Estimating and testing linear models with multiple structural changes. Econometrica, 66, 47–78.
Baum, A., Checherita-Westphal, C., & Rother, P. (2012). Debt and growth: new evidence for the Euro area. ECB Working Paper, 1450. Retrieved from
Beqiraj, E., Fedeli, S., & Forte, F. (2018). Public debt sustainability: An empirical study on Organisation for Economic Co-Operation and Development (OECD) countries. Journal of Macroeconomics, 58, 238 – 248. DOI:
Belguith, S.O., & Omrane, H. (2019). Macroeconomic determinants of public debt growth: A case study for Tunisia. Theoretical and Applied Economics, 4(613), 161-168.
Central Bank of Nigeria (CBN) (2020). Statistical Bulletin, vol. 31.
Chowdhury, A., & Islam, I. (2012). An optimal public debt-to-GDP ratio? G-24 Policy Brief, no. 65.
Chukwu, O.K., Ogbonnaya-Udo, N., & Ubah, C.B. (2021). Effect of public debt on public investment in Nigeria: 1985-2018. Asian Journal of Economics, Business and Accounting, 21(2), 98-114.
Chukwuogor, C., & Ndu, I. (2018). Review of the Nigerian economy 2003 to 2017/18: Prospects for increased sustainable economic development. African Journal of Accounting, Economics, Finance and Banking Research, 11(11), 1-18.
Culling, J. (2017). Debt Sustainability, fiscal space, and growth. Master of Science in Economics Thesis, Department of Economics, University of Otago, New Zealand.
Danjuma, I. (2021). Insurgency, political risk, and foreign direct investment inflows in Nigeria: A Sectorial analysis. CBN Journal of Applied Statistics, 12(2), 27 – 57.
Debt Management Office of Nigeria (2020). Report of the 2020 annual national debt sustainability analysis. Available at:
Debt Management Office of Nigeria (2019). Report of the 2019 annual national debt sustainability analysis. Available at:
Dinneya, G. (2006). Democracy, external debt and growth in Nigeria: An impact analysis under a narrow definition of debt-led growth. Canadian Journal of Political Science, 39(4), 827-853.
Doing Business Report (2020). Economy Profile of Nigeria. World Bank Group.
Fasoranti, M.M., Sunday, K.E., & Haruna, A.T. (2019). Optimal government debt and economic performance in Nigeria. International Journal of Academic Research in Economics and Management Sciences, 8(3), 385–399.
Goedl, M., & Zwick, Ch. (2018). Assessing the stochastic stability of public debt: the case of Austria. Empirica, 45(3), 559-585.
Guarco, A. (2021). International Cooperative Alliance Annual Report.
Guzman, M. (2018). The elements of sovereign debt sustainability analysis. Centre for International Governance Innovation (CIGI). CIGI Papers, no. 196.
IMF (2021). Review of the debt sustainability framework for market access countries. International Monetary Fund (IMF) Policy Paper. Available at:
IMF (2020). Factsheet: Joint World Bank- International Monetary Fund (IMF) debt sustainability framework for low-income countries. Available at: (accessed March 2020).
IMF (2014). Revised guidelines for public debt management. IMF Policy Paper 14/002. Washington, DC: IMF.
Izuaka, M. (2021). Nigeria’s debt problem to get worse; government borrowing ₦5 trillion in 2022. Available at:
Jensen, L. (2021). Sovereign debt vulnerabilities in developing economies which countries are vulnerable and how much debt is at risk? Development Futures Series Working Papers no. 54.
Jilenga, M.T., Xu, H., & Gondje-Dacka, I. (2016). The impact of external debt and foreign direct investment on economic growth: Empirical evidence from Tanzania. International Journal of Financial Research, 7(2), 154 - 162.
Kasele, O., Momeka, L., Bahaya, G., & Ntumwa, B. (2019). Impact of public debt on investment: Case of ECGLC. Journal of Finance and Economics, 7(4), 148-163. DOI:10.12691/jfe-7-4-5
Khanfir, W. (2019). Threshold effect of public debt on economic growth: An empirical investigation for selected North African countries. Economic Alternatives, 3, 429-436.
Knapkova, M., Kiaba, M., & Hudec, S. (2019). Impact of macroeconomic indicators on public debt of Slovak Republic. Journal of Business Economics and Management, 20(4), 734–753.
Kouladoum, J. (2018). External debts and real exchange rates in developing countries: evidence from Chad. Online at Paper No. 88440, posted 19 Aug 2018 02:32 UTC
Kia, A. (2020). Impact of public debt, deficit and debt financing on private investment in a large country: Evidence from the United States. World Journal of Applied Economics, 6(2), 139-161. DOI: 10.22440/wjae.6.2.3
Kamundia, S.W., Gitahi, S., & Mwilaria, S.M. (2015). The effects of public debt on private investments in Kenya. International Journal of Development and Sustainability, 4(8), 860-871.
Krugman, P. (1988). Financing versus forgiving a debt overhang. NBER Working Paper, no. 2486.
Mabula, S., & Mutasa, F. (2019). The effect of public debt on private investment in Tanzania. African Journal of Economic Review, 7(1), 109-135.
Muhammad, F., & Taofik, I. (2018). Public debt management in Nigeria: The impacts of institutional changes after exiting from the Paris Club in 2006. Online at Paper No. 100364, posted 15 May 2020 15:32 UTC
Mugumisi, N. (2021). The impact of public external debt on private investment. Evidence from Zimbabwe under the multi-currency system. Journal of Economic Information, 8(1), 33-47.
Ndoricimpa, A. (2020). Threshold effects of public debt on economic growth in Africa: A new evidence.
Nzeh, I.C. (2020). Public debt and economic growth in Nigeria: investigating the optimal threshold level. Asian Development Policy Review, 8(2), 112 – 127.
Oche, M., Mah, G., & Mongale, I. (2016). The effects of public debt on foreign direct investment in South Africa (1983-2013): An empirical analysis. Risk governance & control: financial markets & institutions, 6(4), 449-456.
Ogunjimi, J. (2019). The impact of public debt on investment: evidence from Nigeria. Development Bank of Nigeria (DBN) Journal of Economics and Sustainable Growth. Available at:
Ogunlana, A.O. (2016). Nigeria and the burden of external debt: the need for debt relief. Available at:
Omodero, C. O. (2019). External debt financing and public capital investment in Nigeria: A critical evaluation. Economics and Business, 33, 111–126.
Omoh, G. (2014). The unending woes of naira exchange rate. Available at:
Omotor, D. (2021). External debt sustainability in West African countries. Review of Economics and Political Science, 6(2), 118-141. DOI 10.1108/REPS-11-2019-0144
Omotosho, B. S., Bawa, S., & Doguwa, S. I. (2016). Determining the optimal public debt threshold for Nigeria. CBN Journal of Applied Statistics, 7(2), 1-25.
Onyele, K.O., & Nwadike, E.C. (2021). Impact of national debt burden on economic stability in Nigeria. Economics and Business, 35, 91 – 106.
Onyele, K. O., & Nwokocha, E. B. (2016). Influence of capital flight on budget implementation in Nigeria. Scientific Papers Series Management, Economic Engineering in Agriculture and Rural Development, 16(4), 247-256.
OPEC (2021). Organisation of Petroleum Exporting Countries (OPEC) monthly oil market report. Available at: file:///C:/Users/HP/Downloads/OPEC_MOMR_November_2021.pdf
Osemeke, N. (2020). The challenges affecting tax collection in Nigerian informal economy: case study of Anambra State. Journal of Accounting and Taxation, 12(2), 61-74.
Pesaran, M. H., Shin, Y., & Smith, R. (2001) Bounds testing approaches to the analysis of level relationships. Journal of Applied Econometrics, 16, 289-326. Available at:
Pescatori, A., Sandri, D., & Simon, J. (2014). Debt and growth: Is there a magic threshold? IMF working paper 14/34, 1-19.
Pokou, K. (2020). Sustainability of public debt and economic growth in Cote d’Ivoire: is there a threshold effect? Journal of Economic Science Research, 3(3), 1 – 12.
Ramu, M.R.A. (2021). Public debt sustainability in sub‑national level: a case of Karnataka. Indian Economic Review.
Reinhart, C. M., & Rogoff, K. S. (2010). Growth in a time of debt. American Economic Review, 100(2), 573-578.
Stiglitz, J.E. (2016). Sovereign debt: Notes on theoretical frameworks and policy analyses. Working Paper 301. New York: Initiative for Policy Dialogue, Columbia University.
Sunday, D.U., Agbaeze, C.C., & Onyele, K.O. (2018). Response of financial development to public debt in Nigeria. Journal of Economics and Business Sciences. Department of Economics, Imo State University, 4(5), 156-164.
Thilanka, H.R.A.C., & Ranjith, J.G. (2018). The impact of public debt on private investment: Sri Lankan Experience. International Journal of Business and Social Research, 8(8), 1-10.
Uremadu, S.O., & Onyele, K.O. (2019). Influence of Fiscal Policy on Gross Domestic Investment (GDI) in Nigeria. Sumerianz Journal of Social Science, 2(7), 74-85.
Were, M., & Mollel, L. (2020). Public debt sustainability and debt dynamics: The case of Tanzania. Research Report in United Nations University (UNU-WIDER). Available at:
World Bank Development Indicators. (2020). Country data for Nigeria. Retrieved from:
World Bank (2019). Debt in low-income countries: evolution, implications, and remedies. Policy Research Working Paper No. 8794, World Bank Group, Washington, DC.
Yussuf, A., & Mohd, S. (2021). The impact of government debt on economic growth in Nigeria. Cogent Economics & Finance, 9:1, 1946249, DOI: 10.1080/23322039.2021.1946249