This article proposes a nonparametric analysis in which the change in the distribution of farm size between two periods is decomposed into several components, and the contributions of subgroups of farms to this change are analyzed. Using data on Israeli family farms, we analyze the changes in the farm size distribution in two separate time periods that are characterized by very different market conditions, focusing on the different contributions of full-time farms and part-time farms to the overall distributional changes. We find that between 1971 and 1981, a period characterized by stability and prosperity, the farm size distribution has shifted to the right with relatively minor changes in higher moments of the distribution. On the other hand, between 1981 and 1995, a largely unfavorable period to Israeli farmers, the change in the distribution was much more complex. While the overall change in the size distribution of farms was smaller in magnitude than in the earlier period, higher moments of the distribution were not less important than the increase in the mean. Between 1971 and 1981 the contributions of full-time farms and part-time farms to the change in the size distribution are quite similar. Between 1981 and 1995, however, full time farms contributed mostly to the growth in the average farm size, while average farm size among part-time farms actually decreased, and their contribution to the variance of farm size was quantitatively larger.