Population in China, Japan and Korea by broad age group, 1950-2050 (cont.) In part this is because groups with traditionally low labour force participation, such as mothers, use part-time employment as a tool to reconcile work and family commitments (OECD, 2007). Workers in part-time employment often still face a penalty compared with full-time workers in terms of pay, job security, training, promotion and lifetime earnings, pension entitlements, or unemployment benefits and/or re-employment assistance in case of unemployment (OECD, 2010b).