In advance of the Cancun meeting of trade ministers convened in
September 2004 to further the Doha Development Agenda (DDA), the heads
of the IMF, OECD, and World Bank declared, "We need a decisive
break with trade policies that hurt economic development. Donors cannot
provide aid to create development opportunities with one hand and then
use trade restrictions to take these opportunities away with the
other--and expect that their development dollars will be
effective." They accorded special emphasis to reducing OECD
agricultural trade protection. "Agriculture is of particular
importance to the economic prospects of many developing countries, and
reforming the current practices in global farm trade holds perhaps the
most immediate scope for bettering the livelihoods of the world's
poor" (Kohler et al. 2004).
The two broad presumptions implicit in the Declaration--that OECD
trade policies, particularly agricultural trade policies, retard
economic progress in poor countries while donor aid effectively promotes
it--have been questioned. Panagariya (2005) and Bhagwati (2005) dismiss
the widespread contention that poor countries stand to gain from
agricultural policy reform by rich countries based on two observations:
(1) the majority of poor countries are net food importers, and (2) most
of the least developed countries enjoy preferential tariff treatment on
their exports to developed countries. Doubts have also been cast on the
assumption that donor aid constitutes an effective mechanism for
promoting economic growth. Easterly, Levine and Roodman (2005) and Rajan
and Subramanian (2007) found little support for claims of a strong,
stable, and positive relationship in the econometric evidence linking
development and aid.
OECD Agricultural Policy and Developing Countries
The potential effects of OECD trade and agricultural policy on
developing countries have generated a large literature of quantitative
analyses, especially since the launch of the DDA in 2001. Most are based
on policy simulations with general equilibrium models (Burfisher 2001;
Bouet et al. 2004; Anderson and Martin 2005; Diao et al. 2005; Hertel
and Keeney 2005; OECD 2006; Polaski 2006), and most emphasize the global
and national totals of potential economic welfare gain, paying much less
attention to sectoral distribution of impacts. Where farm income effects
have been featured (Diao et al. 2005; Anderson and Valenzuela 2006; OECD
2006), the general conclusion is that OECD agricultural policy depresses
farm incomes in developing countries.
Nonetheless, there are some considerations that moderate and could
even reverse this conclusion. Excepting sugar, rice, and cotton,
developing country farmers tend not to specialize in production of those
crop and livestock commodities heavily protected and subsidized in OECD
countries. While it may be argued that this is partly the consequence of
a long history of subsidized OECD agriculture, climatic, and cultural
differences must also be acknowledged. Most of the tropical products
that feature prominently in developing countries are not subject to the
high tariffs and subsidies that characterize developed country
agriculture, thereby weakening the links between OECD farm support and
developing country farm incomes. Even where there is overlap, the
depressing effects of OECD agricultural policy will be felt by poor
country farmers only to the extent that world market prices are
transmitted to local markets where they sell their output. Many
developing country farmers produce for self-consumption or for local
markets that are isolated from world market fluctuations by own-country
trade policies or geographical remoteness and poor market and
transportation infrastructure.
OECD agricultural trade policy reform could reduce farm incomes in
some developing countries through the erosion of the value of
preferential access, as noted by Panagariya (2005) and Bhagwati (2005).
Many developed countries offer developing countries preferential access
to their markets at tariffs that are lower than those applied to
competing exporters. This favorable treatment creates a preference
margin equal to the difference between the Most Favored Nation (MFN)
tariff and the preferential rate. This margin will be reduced and the
associated economic benefits eroded, if MFN applied tariff rates are cut
as part of OECD agricultural policy reform. The consensus emerging from
recent analyses (Bouet et al. 2004; Wainio et al. 2005; Liapis 2007) is
that erosion of the economic value of preferences is potentially an
important problem for some developing countries. Developing country
exporters now receive preferential access only for a short list of
agricultural commodities, namely sugar, bananas, and meat products--a
consequence of EU trade policy.
OECD Development Assistance Policy for Agriculture
Public expenditures on agricultural programs and projects are
largely financed by foreign aid in many developing countries. The
OECD's Development Assistance Committee (DAC) monitors agricultural
aid from its members and multilateral donors, prominently the World
Bank, to developing countries. The DAC defines agriculture sector aid as
funds made available to finance development activities that have
agriculture as their main target. The category incorporates aid
financing of improvements of land and water resources; subsidies to
inputs and agricultural production; agricultural research and extension;
and agricultural policy development.
There is a large literature on the effects of foreign aid on
economy-wide growth but the effects of agriculture sector aid on
agricultural growth have received much less attention from economists.
Norton, Ortiz, and Pardey (1992) included a total aid variable when
estimating agricultural production functions for developing countries,
but they did not distinguish between agriculture-specific aid and other
categories of development assistance. Moreover, the production function
they estimated also included indicators of both the quantity and quality
of agricultural inputs (labor, tractor horsepower, land quality,
education) which themselves could be the specific targets of aid.
Analytical Framework
Has OECD agricultural trade protection and support hurt
agricultural sector performance in developing countries? Has OECD
development assistance for agriculture helped it? Herein we address
these two questions using cross-sectional regression analysis of data
for a sample of eighty-seven developing countries for the period
1986-2004. Following Gardner (2003), we use the annual growth rate of
real agricultural GDP per worker as an indicator of agricultural
performance in developing countries. The key independent variables are
country-specific indicators of OECD agricultural support policy and
normalized agricultural development assistance.
Trend growth rates in agricultural GDP per worker were measured as
the slope coefficients estimated from log-linear trend regressions of
annual data for each developing country in the sample. Real agricultural
GDP data were taken mainly from the World Bank's World Development
Indicators (WDI) and from the United Nations Statistics Division;
agricultural labor force data are from the FAO. (1) We adopt the average
annual real agricultural GDP for 1981-1985 as the base value for the
growth regressions.
Another variable introduced into the regression as an indicator of
initial conditions is the base period share of each country's
agricultural land base devoted to crops benefiting from OECD trade
protection and subsidy. We included this variable to test whether,
independently of the growth effects of OECD trade or aid policy that we
measure separately, those countries exhibiting agricultural production
profiles broadly similar to OECD countries might have better
agricultural growth potential than others. One channel for such
potential is through spillovers from OECD country investments in
production-enhancing agricultural research, typically targeted to the
same crops covered by OECD agricultural support. Another is in the
higher degree of tradability of commodities protected and subsidized in
OECD countries as compared to the bulk of commodities produced in
developing countries. The global transportation, marketing, and
regulatory infrastructure that fosters trade in OECD farm commodities
may create trading opportunities for some developing countries.
The explanatory variable introduced to capture the effect of aid is
the 1986-2004 average annual real value of a country's agriculture
sector aid (DAC), expressed per hectare of agricultural land (FAO) to
achieve comparability across recipient countries. There is some risk in
using sample period averages of wrongly inferring the effects if donor
countries in aggregate happen to favor either low-growth or high-growth
countries in their aid allocations. There are many considerations
affecting a donor country's decision to favor one developing
country over another in its development assistance efforts. In the
specific case of agriculture, an important political consideration
limiting aid flows to certain countries, regardless of their growth
performance, is whether aid fosters increases in their production of
commodities produced in donor countries (de Janvry and Sadoulet 1988).
An indicator of OECD agricultural trade protection calculated by
the OECD as part of its calculation of the Producer Support Estimates
(PSE), the producer Nominal Protection Coefficient (NPC), is the ratio
between the average farm gate price received by an OECD agricultural
producer and the border price net of transportation costs and marketing
margins (OECD 2006). An NPC equal to one implies that producers receive
border prices for their output after adjusting for transportation costs
and thus do not receive production-distorting signals from agricultural
support policies. The NPC is calculated on a commodity-by-commodity
basis for the OECD as a whole as a production-weighted average. The OECD
also calculates the producer Nominal Assistance Coefficient (NAC), the
ratio of farm receipts including support to the market value of
production without support. The NAC includes all forms of producer
support, both the price protection captured by the NPC as well as the
budgetary support for input subsidies, direct income payments, and the
like. We tailored the NPC and NAC variables to each developing country
in the sample by re-weighting the OECD commodity-by-commodity averages
to reflect an individual developing country's output mix (see
McMillan, Zwane, and Ashraf 2005; Roodman 2005). (2)
If a country's preferential access is large, then the effect
of OECD support on the country may be dominated by opportunities to sell
into the protected markets of richer countries. The estimated total
money value of trade preferences a developing country receives from OECD
countries is annual averages of the U.S. dollar values for the period
2001-2003 and comes from Liapis (2007). That study contains estimates of
the value of preferential access for agricultural commodities afforded
to the developing countries by the EU, United States, Japan, and Canada,
which we assume accounts for the greatest share of the value of
preferential access offered by all OECD countries combined. In the base
regression, OECD support is multiplied with a dummy that equals one if
preferences are equivalent to 1% of agricultural GDP or more. The other
dummy distinguishes countries in Sub-Saharan Africa (SSA), a region
where agricultural sector growth has historically lagged behind that in
other parts of the developing world.
Regression Results
Following some initial experimentation we chose one regression
equation to be used as the base version on which we performed a range of
statistical tests. We then estimated a number of alternatives to the
base version by progressively changing the variable list, the sample
period, or the country list. Estimated results are in tables 1 and 2.
The base equation and all of its alternatives omit some variables found
to affect growth in other studies that are insignificant or are
represented indirectly by the base GDP term: indicators of institutional
quality, fertilizer use, availability of tractors, and the share of
population in rural areas.
Regression statistics for the base equation indicate low likelihood
of heteroskedasticity, little multicolinearity, and limited explanatory
power ([R.sup.2] = 0.23). The insignificant coefficient on base period
agricultural GDP per worker suggests there was neither convergence nor
divergence in developing country agricultural GDP growth rates during
1986-2004. The positive and statistically significant parameter
associated with the base area in PSE crops lends credence to the
supposition that developing countries having a greater portion of crops
in competition with crops grown in OECD countries may experience growth
benefits from spill-over effects of OECD investments in agricultural
research or from physical or regulatory infrastructure that facilitates
global trade in PSE commodities.
The coefficient on the aid variable is negative and statistically
significant in the base and most alternative specifications. Negative
aid coefficients might be dismissed as merely showing that donor
countries target their aid to low-growth countries. That could explain
our result, but we doubt it. We find little evidence of simultaneity; a
two-equation model to estimate simultaneously effects of aid on growth
and the allocation of aid failed to explain the allocation of aid. Only
two alternative specifications call into question a negative effect of
aid on agricultural GDP growth: when a cross-term with the SSA dummy is
included, and when the data relate exclusively to countries for which
aid is large relative to agricultural GDP. The estimated coefficient
obtained for the aid-SSA cross-term is statistically significant and
positive. An estimated zero net effect of aid on growth in SSA countries
is implied by the sum of the coefficients on the aid variable and that
obtained for the aid-SSA cross-term in the same specification. Positive,
but generally statistically insignificant, aid coefficients were
obtained in alternatives using only data for those countries where aid
represents a relatively higher share of agricultural GDP. We exclude the
possibility of increasing returns to aid after finding an insignificant
parameter on the square of aid when this variable is added to the base
model.
The finding of a statistically significant and reasonably stable
negative coefficient on the aid variable was surprising. The analysis
required to obtain a fully satisfactory understanding of its economic
significance is beyond the scope of this article. The complications
begin with a measurement question. Agricultural GDP measures the returns
to primary factors, namely, land, labor, and capital and is normally
calculated as market revenues plus subsidies minus the costs of
intermediate inputs and taxes. Conceptually, at least part of sector aid
should be considered as a subsidy. In national economic accounting,
foreign aid flows into a country will show up in national GDP estimates
but not sector-specific aid in sector GDE Thus, the data can only reveal
the effects of aid on agricultural GDP resulting from induced increases
in farm production and the knock-on impacts on the market prices of
agricultural inputs and outputs. These depend critically on elasticities
and the nature of the supply shift provoked by aid-financed subsidies, a
familiar conundrum in the analysis of the effects of technical change on
farm income (Alston and Martin 1995).
The estimated coefficient for the NPC variable was negative in the
base equation, as were the estimates for it and the NAC variable in most
alternative specifications--findings consistent with the idea that
developed country agricultural policies depress farm income growth in
developing countries. However, their statistical significance was low.
The tests over various sub-samples and explicit cross-terms indicate
that the effect may not be constant; there may be cause to separate the
experiment dependent on country characteristics rather than assume a
common effect. At the same time, using the NAC, a more comprehensive
measure of agriculture support than is the NPC, did not increase
explanatory power. Moreover, neither the magnitude nor the statistical
significance of the coefficient changed very much in that alternative.
These results are consistent with findings from several recent GE
analyses showing that gains to developing countries from OECD
agricultural policy reform would come mainly from the reductions in
price support resulting from cuts in agricultural tariffs rather than
from reductions in other forms of support OECD governments provide their
farmers (Anderson and Martin 2005; OECD 2006).
The estimated coefficient for the NPC variable crossed with the
preference dummy gives some credence to claims that access to protected,
high-priced OECD commodity markets improves agricultural sector
performance in developing countries but, again, only with considerable
uncertainty. Ignoring this uncertainty, the cross-term coefficients
obtained in most specifications and subsets of data suggest that if OECD
policies have negative effects in general, the effect is nearly
eliminated in the case that preferential treatment is substantial.
Moreover, the greater the value of preferences relative to agricultural
GDP, the greater the possibility that the net effect may even be
positive. Thus, we observe weak evidence that granting meaningful
preferential access to OECD markets may offset any small negative
effects of the initial distortion caused by OECD agricultural policies,
but less evidence that the net effect may spur growth beyond what would
have occurred in the complete absence of distorting OECD agricultural
policies.
Summary
The evidence presented here indicates that the negative effects of
agricultural aid on growth in measured agricultural GDP per worker
outweigh the positive effects in general. Estimated aid coefficients are
negative and statistically significant, possibly excluding SSA or
aid-dependent countries where the effect may be approximately zero. The
negative aid effect could result from induced reductions in local market
prices of commodities whose production increases as a consequence of
aid--an outcome that may well have been the objective of aid-financed
investments in the first place. The strong positive effect of the degree
of overlap between a developing country's crop planting patterns
and OECD crop area suggests another reason for a negative aid effect;
agricultural aid directed toward traditional, non-OECD crops may rob
developing country farmers of access to spill-over effects.
The effect of OECD agricultural trade and subsidy policies is less
clear. The relevant parameter is negative in the base regression and
most alternatives, but the large error undermines certainty. Thus, we
find tenuous evidence to support assertions that OECD agricultural
policies hamper growth in agricultural GDP per worker in developing
countries. However even in the event there is an effect, it may be
offset in those cases where preferential access is large enough relative
to the size of the sector.
The authors would like to thank Stefan Tangermann, Martina Garcia,
and Bryce Wood for useful comments on an earlier draft.
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(1) Serious measurement errors are likely. Gardner (2005) points to
often-dubious assumptions made in estimating agricultural value added,
such as estimated capital flows. Labor force statistics are often based
largely on interpolation or extrapolation.
(2) To calculate indicators based on NPCs and NACs, developing
countries' commodity production value weights were evaluated at the
world prices used in the OECD's own calculations. Pasture area is
included to reflect support to ruminants (beef, sheepmeat, and dairy).
The calculation is based exclusively on the commodities of the
OECD's support estimates, but is adjusted by the share of these
commodities in agricultural land to reflect the share of crops appearing
in OECD support data in a developing country's total production.
Data measuring crop and pasture area are from the FAO.
Joe Dewbre is Senior Economist in the Agriculture and Development
Division of the OECD's Trade and Agriculture Directorate. Wyatt
Thompson is Assistant Professor at the University of Missouri, Columbia.
Joshua Dewbre is pursuing graduate studies in development economics at
American University, Washington DC.
This article was presented in a principal paper session at the AAEA
annual meeting (Portland, OR, July 2007). The articles in these sessions
are not subjected to the journal's standard refereeing process.
Table 1. Base Regression of Growth in Agri-cultural GDP per Worker
Explanatory Parameter Error t-Statistic
Variable
AID per hectare of -0.003 0.001 -2.85
agricultural land
Country-specific -0.005 0.004 -1.31
NPC
NPC x Pref. Dummy 0.004 0.006 0.67
(>1% of Ag
GDP)
Share of PSE crops 0.005 0.001 3.81
in total ag. land
Real agriculture -0.001 0.002 -0.53
GDP in base
period
Sub-Saharan Africa -0.006 0.004 -1.56
dummy
Note: Independent variables are in logarithmic form.
Table 2. Regressing Agricultural GDP per Worker Growth Over
Subsets of Data and Alternative Specifications
Aid
Coeff. Error
Base regression, subsets of data
Including only those countries where:
Ag GDP < $750/worker -0.002 0.002
Ag GDP >$1000/worker -0.003 0.001
Population < 3.8 million -0.003 0.001
Population > 4.5 million -0.003 0.001
Only those countries where aid to agriculture share in agricultural
GDP was:
... below 1 % -0.002 0.002
... below 2.5% -0.003 0.001
... below 5% -0.003 0.001
... above 1 % -0.001 0.002
... above 2.5 % 0.002 0.003
... above 5% 0.006 0.004
Half period: 1986-1994 -0.002 0.002
Half period: 1995-2004 -0.003 0.001
Alternative variables, base data
NAC instead of NPC -0.003 0.001
Threshold for preference dummy instead of > 1 % of GDP set at:
... at least 0.5% -0.003 0.001
... at least 2% -0.003 0.001
... at least 5% -0.002 0.001
With SSA cross terms 0.004 0.002
non-SSA coefficients -0.003 0.001
NPC
Coeff. Error
Base regression, subsets of data
Including only those countries where:
Ag GDP < $750/worker -0.004 0.005
Ag GDP >$1000/worker 0.000 0.009
Population < 3.8 million -0.010 0.011
Population > 4.5 million -0.005 0.005
Only those countries where aid to agriculture share in agricultural
GDP was:
... below 1 % -0.010 0.008
... below 2.5% -0.010 0.006
... below 5% -0.009 0.004
... above 1 % -0.002 0.005
... above 2.5 % 0.001 0.006
... above 5% 0.009 0.008
Half period: 1986-1994 -0.016 0.008
Half period: 1995-2004 0.003 0.006
Alternative variables, base data
NAC instead of NPC -0.005 0.004
Threshold for preference dummy instead of > 1 % of GDP set at:
... at least 0.5% -0.003 0.004
... at least 2% -0.006 0.004
... at least 5% -0.005 0.004
With SSA cross terms -0.002 0.008
non-SSA coefficients -0.003 0.005
NPC x Pref.
Coeff. Error
Base regression, subsets of data
Including only those countries where:
Ag GDP < $750/worker 0.024 0.016
Ag GDP >$1000/worker -0.003 0.011
Population < 3.8 million 0.009 0.012
Population > 4.5 million 0.003 0.013
Only those countries where aid to agriculture share in agricultural
GDP was:
... below 1 % 0.020 0.016
... below 2.5% -0.003 0.013
... below 5% -0.004 0.008
... above 1 % 0.002 0.007
... above 2.5 % 0.011 0.008
... above 5% 0.020 0.012
Half period: 1986-1994 0.012 0.014
Half period: 1995-2004 0.001 0.010
Alternative variables, base data
NAC instead of NPC 0.004 0.006
Threshold for preference dummy instead of > 1 % of GDP set at:
... at least 0.5% -0.001 0.006
... at least 2% 0.009 0.007
... at least 5% 0.009 0.008
With SSA cross terms NA NA
non-SSA coefficients 0.002 0.006
[R.sup.2]
Base regression, subsets of data
Including only those countries where:
Ag GDP < $750/worker 0.19
Ag GDP >$1000/worker 0.33
Population < 3.8 million 0.42
Population > 4.5 million 0.18
Only those countries where aid to agriculture share in agricultural
GDP was:
... below 1 % 0.32
... below 2.5% 0.33
... below 5% 0.36
... above 1 % 0.13
... above 2.5 % 0.13
... above 5% 0.33
Half period: 1986-1994 0.20
Half period: 1995-2004 0.12
Alternative variables, base data
NAC instead of NPC 0.23
Threshold for preference dummy instead of > 1 % of GDP set at:
... at least 0.5% 0.22
... at least 2% 0.24
... at least 5% 0.24
With SSA cross terms 0.26
non-SSA coefficients
Note: The column headings in this table abbreviate the variable names
that are more fully labeled in the top three rows of table 1. The
complete list of variables in the base equation was retained in all
of these alternatives, but only those results relating to the key
policy variables are reported here. The lop half of the table
represents results obtained when the base equation was estimated over
different subsets of observations. The second half of the table
represents results obtained using the same sample as for the base
equation while changing or adding variables. The last two rows
together contain the complete set of results when including SSA
cross-terms in the regression.
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