When Do People Work?: An analysis on work timing between regular and non-regular workers

This paper uses a Japanese time use survey to examine how the timing of work in Japan has changed since the 1990s, focusing on changes in labor market regulation, open-hour legislation, and a huge negative demand shock that hit the economy from the early 1990s. We find a noteworthy increase in the share of employees working at unusual hours (late night and early morning) over a period of a decade since the mid 1990s. When controlling for changes in hours worked, however, we find that the notable increase in the fraction of people working at unusual hours was for low-income non-regular workers (part time, temporary and contract workers), while relatively higher-income regular employees' work timing remains stable. These observations imply that there is a trend of diversification of work timing in Japan between regular and non-regular workers. An Oaxaca-Blinder type decomposition suggests that increased demand for services and goods by regular employees at unusual hours, possibly due to more implementation of the five-day workweek since the 1990s, partially explains the rise in the employment rate of non-regular employees at unusual times.