探究台灣製造業實質勞動生產力與實質薪資脫鉤的關稅與匯率政策因素

THE DECOUPLING OF WAGE GROWTH AND PRODUCTIVITY GROWTH IN TAIWAN’S MANUFACTURING SECTOR: A POLICY PERSPECTIVE

本研究探討製造業中台灣實質勞動生產力與實質薪資脫鉤的政策因素。利用1996年至2015年製造業下各中類行業資料，我們發現影響生產力薪資差擴大的因素為消費與產出相對價格的擴大與加價的增加；勞動份額與薪資份額主要透過產業結構改變影響，但此效果在樣本時間內不顯著。進一步探討製造業中相對價格擴大的原因，我們發現平均進口關稅下降、出口有效匯率相對升值在樣本時間內扮演重要的角色。其影響途徑主要透過以台幣計價之產出價格的下跌。而對中國大陸投資增加間接影響產出價格下跌。產業加價雖減少相對價格擴大卻直接影響生產力薪資差，效果由後者主導。進口中間財關稅的下降則減緩薪資差擴大趨勢。此結果符合獨占性廠商選擇品質模型預測。

This paper examines why the growth of real wages has trailed the growth of labor productivity (real GDP per labor hour) in the past two decades in Taiwan’s manufacturing sector. Using industry-level data from 1996 to 2015, we find that the decline in the labor share, and in the share of wages to labor compensation, mainly explain the differences between labor productivity and real wages across industries. The within-industry variations are mainly caused by variation in the relative prices between consumption and output and by variation in markup. Furthermore, we build a trade model of monopolistic competition with quality choices to clarify the channels through which tariffs and exchange rates affect output prices. Using an empirical model obtained from our theoretical model, we show that appreciation of the effective export exchange rates and a drop of the average import tariff increase the gap between labor productivity and real wages. The rise of Taiwanese direct investment in China indirectly increases the gap through increased exports. A reduction of the effective imported-intermediate good tariffs, however, lessens the gap. These findings are consistent with the implications of our theoretical model.