わが国稲作生産性の伸びはゼロとなるか？

総合生産性，技術変化およびキャッチ・アップ効果の計測を通じて

抄録

The purpose of this paper is to show the evidence that the growth rate of Japan's rice productivity will decline to zero percent in the future. An analytical framework measured the total factor productivity (TFP) of rice farms in 43 Japanese prefectures from 1957 to 1995 employing the input-oriented Malmquist TFP indices through comparison of TFP growth between the pre-Rice Acreage Control Programmes period 1957-1970 (hereafter pre-RACP period) and the Rice Acreage Control Programmes period 1970-1995 (hereafter RACP period). The TFP change is decomposed into two components: (1) the catching-up effect (the overall technical efficiency change); (2) the technical change. Linear programming techniques are used in calculating these indices. The empirical re-sults can be summarized as follows. First, Japan's annual TFP growth during the RACP period was stagnant and lower than that during the pre-RACP period. Second, the technical progress was dominant compared to the catching-up effect in both the pre-RACP and RACP periods, then stagnation in TFP growth during the RACP period was attributable to a slowdown in technical progress in the same period. Third, a decline in the catching-up effect observed during the pre-RACP period was due to rapid technical progress and a rise in the catching-up effect during the RACP period was due to a slowdown in technical progress. These results suggest that the growth rate for rice productivity in Japan will decline to zero percent in the future.