Sri Lanka - Labour Force Survey - 2010

2.1 Sampling plan and the sampling frame A two stage stratified sampling procedure was adopted to select a sample of 22,500 housing units to be enumerated in the survey. The master sampling frame prepared for 2001 Census of Population and Housing was used as the sampling frame for the selection of sample for the labour force survey 2010.This main frame was updated after the Tsunami incident in 2007 using quick count method. 2.2 Sample size The quarterly survey was conducted since 1990 using a sample of 2,000 housing units per quarter in areas other than North and East, and the sample size was increased to 4,000 housing units per quarter in 1996 and continued thereafter. However, in 1992 and 1997, an annual sample of 20,000 housing units was selected to give reliable estimates of district level. In 2004 again 20,000 housing units were selected for the survey. However, in order to provide district level estimates precisely, it was decided to use 20,000 - 25,000 housing units as the annual sample from 2006. As such, in 2010, the annual sample of 22,500 housing units were selected. 2.3 Sample Allocation In 2010, 2,250 Primary Sampling Units (PSU's) are allocated to each district and each sector by using the Neymann Allocation method which considers the variance of unemployment rate as usually. The allocated sample for each district then equally distributed among the 12 months. Table 1 gives the sample distributions by district for year 2010 Table 1: Sample allocation by district - 2010 District Housing District Housing Units Units Total 22,500 Mullaitivu 390 Colombo 2,150 Kilinochchi 360 Gampaha 1,920 Batticaloa 560 Kalutara 1,210 Ampara 900 Kandy 1,400 Trincomalee 390 Matale 610 Kurunegala 1,680 Nuwara Eliya 600 Puttalam 840 Galle 1,200 Anuradhapura 960 Matara 970 Polonnaruwa 500 Hambantota 840 Badulla 860 Jaffna 720 Moneragala 550 Mannar 390 Ratnapura 1,160 Vavuniya 390 Kegalle 950 2.4 Selection of Primary Sampling Units (PSU) Primary sampling units are the census blocks prepared for the Census of Population and Housing - 2001. The sample frame, which was updated after Tsunami has been used for the selection of primary sampling units. 2.5 Selection of Secondary Sampling Units (SSU) Secondary Sampling Units are the housing units in the selected 2,250 primary sampling units (census blocks). From each primary sampling unit 10 housing units (SSU) are selected for the survey using random sampling method.


In 2009, the field work of the survey for the year 2010 was done in all twelve months in 2010.Even though it was planned to conduct the labour force survey in Northern and Eastern provinces, the survey could not be conducted properly in Northern province due to the prevailing conditions. In year 2010 the survey was carried out in Eastern province successfully as in 2009.Therefore, this report is based on an annual sample of 20,250 housing units, excluding only Northern province provoding national, provincial and district level estimates with a stipulated standard errors of labour force characteristics as reported in the relevant reference periods of each 12 months of the year 2010. This survey covers persons living in housing units only and, it excludes the institutional population.