INDIA - Periodic Labour Force Survey (PLFS), Calendar Year 2021 (Jan21 Dec21)

A rotational panel sampling design will be used in urban area. The rotational scheme will be of two years duration to accommodate the changes in the urban frame in the intracensal period; in the sense that the sampling frames for both rural and urban areas will remain unchanged for every two-year duration. In this rotational panel scheme each selected household in urban areas
will be visited four times - one with first visit schedule and other three with revisit schedule. The estimates can be given for successive quarters without any break in the series (starting from the fifth quarter), ensuring a 75% matching between consecutive quarters. Regression based estimates will not be generated. Instead, usual traditional design based estimates will be
generated. The proposed design aims at generating quarterly estimates of level and change parameters of some important labour force indicators (LFPR, WPR & UR) based on CWS data in urban areas and annual estimates of level parameters based on usual status for both rural and urban areas in the line of employment & unemployment survey of NSS quinquennial round.

Rotational panel design for urban areas

i. The initial rotational panel will be for two years, where only 25% FSUs of urban annual allocation will be covered in the first quarter (Panel P11) with detail listing and canvassing of visit 1 schedule in the selected households; where Pij indicates the panel belonging to jthquarter of the ith two-year period of rotation.
ii. Another 25% FSUs will be covered in the second quarter (Panel P12) for taking up visit 1 schedule and revisit schedule will be canvassed in the selected households of Panel P11.
iii. A new panel P13 of 25% FSUs will be surveyed in third quarter with visit 1 schedule andrevisit schedules will be nvassed in the households of panels P11 & P12.
iv. In the fourth quarter, households of panels P11, P12 & P13 will be surveyed with revisit schedule and a new panel P14 with 25% FSUs for visit 1 schedule.
v. In the subsequent quarters of second year 75% FSUs (3 panels - P12, P13 & P14) will be common and an earlier panel (P11) will be replaced by a new panel (P15) for canvassingvisit 1 schedule. This will continue till 8th quarter.
vi. All the FSUs of the panels P11, P12, ...., P18 (each of which is with 25% of FSUs) will beselected before commencement of survey in the first quarter.
vii. At the end of the second year of each two-year duration, updated frame will be used for both rural and urban areas.
viii. FSUs of another set of panels P21, P22, ..., P28 selected from the updated frame will be made ready before commencement of first quarter of third year (first quarter of the second two year duration). These panels P21 to P28 will take care of the changes in the urban frame during the intracensal period.
ix. In the ninth quarter (first quarter of the second two-year duration), panel P21 selected from the updated frame will be introduced and the panels P16, P17 and P18 of the old frame will be surveyed.
x. This scheme will continue for another 2 years with the introduction of panels P22 to P28 each in one quarter for the subsequent 7 quarters till the end of the fourth year (second year of the two-year period).
xi. This scheme of rotation of panels will enable generation of estimates of change parameters with 75% matching and 25% of unmatched samples from fifth quarter onwards.
xii. One of the main advantages of this plan of rotation is that there will not be any break in the series of estimates of the change parameters starting from 5th quarter.
xiii. Since major changes in the rural-urban frame occurs in the Census years (say for the year 2023-24), provision is to be made to generate estimates without break in the series of estimates considering panels from pre and post-census frames.

Rural samples
For rural areas, samples for all the 8 quarters will be selected before commencement of survey for each two-year period, while the frame remains same for this duration. In each quarter, only 25% FSUs of annual allocation (as is done in each sub-round of NSS rounds) will be covered in rural areas so that independent estimates can be generated for each quarter. For this purpose,
quarterly allocation will be multiple of 2 for drawing interpenetrating sub-samples


State/UT level sample size will be allocated between two sectors in proportion to population as per Census 2011 with double weightage to urban sector in general. Within eachsector of a State/UT, the respective sample size will be allocated to the different strata (in the case of urban areas) and strata/ sub-strata (in the case of rural areas) in proportion to the population as per Census 2011. Urban allocations at stratum level will be adjusted to multiples of 8 with a minimum sample size of 8 (for 4 panels, each of size at least 2). Rural allocation for each stratum will also be multiple of 8 with minimum sample size of 8 (for 4 quarters, each of size 2). For special stratum formed in rural areas of Nagaland as discussed in para 1.4.8, 16 FSUswill be allocated.

It may be noted that quarterly allocation of FSUs will be same for an NSS state-region although 25% of the urban FSUs will rotate over the quarters according to the rotational scheme.However, quarterly allocation of urban FSUs for FOD regions and FOD sub-regions may vary over the quarters since new FSUs entering the sample according to the rotational scheme may or may not belong to the same FOD region or FOD sub-region.