aid for trade programmes have a critical role to play along all of these policies however the importance of agriculture varies considerably among developing countries even within one region for example agriculture accounts for of the national gdp in liberia in guineabissau and in the democratic republic of the congo but less than in oilrich middleincome countries like gabon the republic of congo and equatorial guinea usaid a declining share for agriculture in national employment and gdp is an inevitable consequence of economic progress byerlee et al