measures were available in both surveys. Following to the same time frame for the administration of the 1985 survey, the 2005 fieldwork was conducted between November 2004 and February 2005 in order to eliminate seasonality effects that may affect over-time comparisons. In order to differentiate the impact of NTX production based on timing and duration of adoption, we rely on 1985 and 2005 production figures and retrospective information collected in 2005 concerning annual NTX cultivation patterns dating back to 1979 to define adoption categories. Table 1 presents the distribution of the sample households according to their snow pea adoption status.

_Adoption_ is defined by having cultivated snow peas for at least 2 agricultural seasons in the period of 1979-2005, and _early adoption_ is equivalent to snow pea adoption by the 1984-1985 agricultural season, i.e. the season on which the baseline survey collected data and by when the majority of smallholders had already adopted. We further distinguish between e _arly adopter leavers_ , i.e. early adopters that have not cultivated snow peas in the two seasons preceding 2005, and _early adopter stayers,_ who adopted snow peas by 1985 and continued its production through 2005.<sup>21</sup> Henceforth, we refer to early adopter stayers and early adopter leavers as stayers and leavers, respectively.<sup>22</sup> Tables 2 and 3 present descriptive statistics by household snow pea adoption status. _Never_ refers to non-adopters, _Ever_ accounts for snow pea adoption at any point between 1979 and 2005 for at least 2 years, and _Late_ identifies late adopters. Table 2 depicts household involvement in NTX production over time. We observe that, on average, early adopters started cultivating snow peas by 1981. While the average years of cultivation among stayers exceeded 20 years in the period of 1979-2005, the comparable figure was just above 13 years for leavers, who, on average, left snow pea production by 1994. For late adopters, the average figure for the first year of snow pea cultivation was 1988. Trends in cooperative membership often mirror NTX adoption histories, particularly in the early years when NTX adoption was possible almost exclusively through the coop. While withdrawal from snow pea production generally implied severance from the cooperative, consistent cultivation of the crop, generally reflected sustained involvement in _Cuatro Pinos_ and good relations with, or participation in, its management.

Table 3 reports changes in household characteristics pertaining to human capital, consumption status, and asset position. A finding that is perhaps consistent with the implications of different snow pea adoption pathways is that over time, stayers increased their landholdings by close to 30 percent, while the average amount of land owned by leavers declined by 17 percent between 1985 and 2005. In the same period, the trends in land ownership among _non-adopters_ and _late adopters_ were rather stagnant. Furthermore, the comparisons of household highest and average years of education across adoption categories reveals that in comparison to non-adopters, the changes in the average values for both variables were positive and statistically significant among leavers, who, on average, also recorded the highest levels of educational attainment in 2005.

> 21 If a similar rule to distinguish between leavers and stayers is imposed among late adopters, approximately twothirds of the late adopters would belong to the late adopter leaver category, potentially rendering the size of the late adopter stayer sample too restrictive for meaningful comparisons. Hence, we choose not to distinguish between leavers and stayers within the group of late adopters.

> 22 In order to respond possible concerns about a degree of discretion introduced by this classification, we tried different thresholds with no substantive changes in the results.

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