Tokyo - Japan's unemployment rate climbed by 0.1 percentage points to 4.2 per cent in December, the government said Friday.

The number of unemployed people decreased by 170,000 from a year earlier to 2.59 million, falling year-on-year for the 31st consecutive month, the Ministry of Internal Affairs and Communications said.

Medical and welfare services added 400,000 jobs to employ 7.23 million people while manufacturers shed 350,000 positions to 998,000 and the construction industry saw a decrease of 140,000 to reach 490,000, the ministry said.

Analysts say, however, one of the country's most serious issues in the past decade is not unemployment rates but unstable forms of employment especially among women and young people.

The proportion of temporary and part-time workers in the labour force hit a record high in 2011 of 35 per cent, up 0.8 percentage points from the previous year.

Meanwhile, the availability of jobs, measured as a ratio of job offers per job seekers, climbed 0.02 points from the previous month to 0.82 in December, the Ministry of Health, Labour and Welfare said. - Sapa-dpa