Title: External debt and growth: An econometric study
1External debt and growth An econometric study
- Marianna KoliIDPM, University of Manchester
- ESDS International Conference
- London, 3 December, 2007
2Research objectives
- To assess the significance of debt as a
determinant of growth - To test the debt overhang hypothesis
- To find the critical debt ratios where the impact
of debt on growth becomes negative
3Context
- Growth
- Mainstream variable
- Often proxy for development
- Debt
- Instrument of public dev. discourse
- Need hard evidence of real situation
- Little research into exact critical ratios
- Debt overhang hypothesis (Krugman)
4Debt overhang hypothesis
GDP per capita growth
Debt/GDP
Growth-maximising debt level
5Previous literature
- A wealth of studies on determinants of growth
- Large country samples (100)
- Some studies on debt/growth and debt overhang
hypothesis - Pre-2000 papers 10-30 countries
- Recent papers 20-100 countries
6Original contributions of this study
- Middle-income countries only
- Smaller subgroups of countries
- Lat Am/non-Lat Am
- Severely/moderately/less indebted
- Determination of critical debt level
- New data compared to previous literature on same
topic
7Sample
- 25 middle-income countries as classified by UN
based on GDP pc - Middle-income versus low-income
- Lower levels of absolute poverty, HIV and other
urgent wide-scale problems - Better possibilities for strategic planning
- Better institutions
- Better government?
8Sample
- Exclusions
- Population less than 1 000 000 (islands)
- Independence after 1960 (EECA, SSA)
- China excluded for poor data availability
- 85 data points of 7700 (1.1)had to be estimated
using combination method two moving averages and
two econometric techniques, with equal weights
9Subgroups
- Indebtedness
- Severely/moderately/less indebted
- Effect of debt level on debt/growth relationship
- Latin America
- Endemic debt crises in 1980s
- To find out whether debt/growth relationship is
different in Latin America
10Methodology
- Regression with fixed effects
- chosen through logical method and OLS/FE/RE
diagnostic statistics comparison - Robustness tested through country groups
11Results
- Significance in several subgroups debt/GDP, debt
service/X, short-term debt/total debt, budget
balance/GDP, terms of trade, investment/GDP and
economic openness - Results reflect the current theories about
financial crises in middle-income countries
12Results debt variables
- External debt/GDP is highly significant in all
groups except non-Latin America - External debt without lag gives U-shaped Laffer
curve - External debt with lag gives inverted U-shaped
curve - All sub-samples give same shape for curve
13Results Cubic Laffer curve
Lagged variables
Non-lagged variables
GDP per capita growth
Debt/GDP
Growth-maximising debt level
14Results insignificant variables
- Education, population growth, tax revenue/GDP,
economic freedom - Solow model variables found insignificant,
possibly because of heavy focus of model on debt - Taxes and economic freedom possibly neutralised
by other variables (budget balance, investment)
15Results Being in Latin America
- Small number of significant variables
- Significant variables external debt, budget
balance and short-term debt - Debt service is insignificant
- Different causes of growth slowdowns
- Lat Am debt overhang
- Non-Lat Am debt service crowds out investment,
reducing growth
16Results Indebtedness level
- SICs debt, stability, openness (negative!)
- LICs debt, investment and stability
- MICs debt, ST debt, terms of trade, education,
economic openness, investment rate - Conclusion debt is significant in all groups,
but reasons may be different
17Results for debt overhang
- Mixed evidence for DOH (total of 24 squared
coefficients, of which 12 significant, of which 6
negative) - Some evidence for DOH found in all subgroups
except Less Indebted Countries
18Critical debt ratios(90 confidence interval)
19Explanation of critical ratios debt/GDP
- High error margins in some groups, but all
critical debt/GDP ratios over 100 - Higher thresholds than earlier research
improved debt tolerance? - Previous studies included 1970s and included both
low- and middle-income countries - Latin America shows lower tolerance than whole
sample of 25 countries
20Explanation of critical ratios DS/X
- We find lower critical ratios than Pattillo et al
(2002) - Possibly explained partly by sample composition
high exporters give low DS/X ratios (e.g.
Thailand, Philippines) - No clear statistical explanation for lower ratios
does this mean debt service tolerance has
fallen?
21Laffer curve findings debt/GDP
- Four countries found on wrong side of the Laffer
curve during 1980-2001 - Bolivia (1986-87)
- Jordan (1987, 1989-1995)
- Panama (1988-1989)
- Syria (1983-2001)
- All but Bolivia are still severely indebted
22Laffer curve findings DS/X
- Seven countries exceed the 30 mark for longer
periods of time, mostly Lat Am - Argentina (range 25-80)
- Bolivia (30-60)
- Brazil (20-80)
- Chile (15-70)
- Hungary (20-50)
- Mexico (20-50)
- Peru (10-50)
23Conclusions
- Crisis avoidance and growth objectives are
equally important - Infant institutions argument is valid,
particularly in SICs - Policies should be tailored to country
circumstances - Model may be specific to conditions where debt is
important