households in each EA that are using improved seeds, chemical fertilizers, organic manure or pesticides.

# **4. Results**

# **Descriptive statistics**

The descriptive statistics are presented in tables 1 to 4, both by country and by AEZ.

# **The agricultural endowments**

In table 1 b, row 1, we see that the average AEP per ha across all the countries is 740 dollars per ha, evaluated at international commodity prices prevailing between 2005 and 2008. This appears to be low, as most of the farmers in the countries analyzed are far from intermediate input levels used to calculate the AEP. When we calculate the AEP per person living in the EAs the average is only 394dollars, which shows that effective population pressure relative the AEP is also high. We have argued in the last section that AEP per person is a superior measure of population pressure than AEP/ha. Map 1 shows the AEPs/ha for the EAs in our sample across our six countries.

Table 1 a and 1 b here It is immediately apparent that areas of high potential areas are most prevalent in pervasive in Uganda and Central and Southern Malawi. In other countries it is mostly light green areas with potential between 478 and 786 dollars per ha that are scattered across the countries, rather than the darker green areas with higher potential. In Ethiopia and Nigeria there are also many are many brown areas that have low potential, mainly in the dry northern parts of each of these countries. In Niger of course low potential areas dominate in the entire country.

Insert map 1 here.

Consistent with the insights from map 4, Uganda shows the highest AEP per ha at $1,878, followed by Malawi ($999), Tanzania (786), Ethiopia ($691), Nigeria ($657), and finally Niger ($478), which is not surprising given the aridity of the country. It is striking that Uganda has almost twice the AEP/ha as the next country, Malawi. Note that the AEP only takes account of the first season, and that Uganda has by far the highest cropping intensity (table 6). Therefore the real advantage of Uganda is even more striking.

The rural population densities over the sample AEZs are the highest in Uganda and the lowest in Tanzania. Nigeria follows at 218 people/sqkm, Malawi at 182 and Ethiopia at 174. Very low population densities are observed in Tanzania (59) and Niger (60). Our sample estimates of rural population density, the rural population densities across the entire countries. The extreme case is Uganda with a rural population density for the AEZs of 266, while the overall population density across rural and urban areas, according the WDI (World Development Indicators), is only 176 persons/sqkm. The reason is that the EAs in the surveys have been selected with probability proportional to their population, which means that the highly populated rural areas are represented more strongly in the sample than the low density ones.

In the second row the AEP /ha (multiplied by 100) has been divided by the rural population density to arrive at the AEP per person. Across all the countries it is only $394 per rural person. Map 2 shows the AEP per rural person across all of the countries. The concentration of AEPs in red suggests that Tanzania has low agro-ecological population pressure. It is also surprisingly suggest that Niger has among the highest AEP per person, and therefore low agro-ecological potential across the sample countries. Uganda, despite its high population density also has relatively low 11