Vincent de Leijster

121 Chronosequence analysis of economic performance of agroforestry coffee farms in Colombia 6 placed in alley formation on the farm or ‘Living fences’, where the majority of the trees were bordering the farm. In addition, on 11 monoculture and 56 agroforestry farms we used vegetation plots of 20 m by 20 m to measure the vegetation structure. Within the plots, we identified all trees with a diameter at breast height (DBH) >5 cm to species level. Of each individual tree, we measured DBH with a measuring tape, and height using a Nikon Forestry Hypsometer. These raw data were used to calculate carbon stock (section 6.2.4.1). 6.2.3 Economic performance indicators We chose to assess economic performance by determining the development of four economic performance indicators: coffee gross revenue, coffee net revenue, actual net revenue and potential net revenue. For all these indicators, the raw data was standardized to annual monetary values on a per hectare basis. Most variables were collected for each farm, except when in some specific cases farmers were not able to provide accurate information from own records of the specific cost or benefit components. In these cases, we extrapolated the average value from those farmers who provided accurate information (see below for further explanation). The market prices of agrochemical products were obtained from two agrochemical shops in Guática and Santuario (see appendix).