2003-04 and 2010-11 (for Nepal) and the LFS (for Pakistan) count activities such as fetching water and collecting firewood and dung as employment, whereas sources in other countries do not. To ensure comparability, we excluded such activities in all countries.

The structure and framing of employment questions may vary even within the same primary source. In Afghanistan and Pakistan, for example, employment modules are different for males and females. In Bangladesh, the HIES asks employment questions in two different modules. A first set of questions is asked in the roster module while a second set appears later (module 5: A & B). This breakdown sometimes results in inconsistent responses.

A second difference in the definition of employment across data sources concerns the identification of the main activity of the respondent. For example, in the Bangladesh HIES each respondent lists several activities he or she was involved in, but only the activity absorbing the most time is registered. In India, on the other hand, the NSS makes a distinction between ‘principal’ and ‘subsidiary’ activities based on the duration of the work. We include only the ‘principal’ status in our dataset.

The recall period is a third important difference between data sources. For example, in Afghanistan the 2007-08 NRVA uses a recall period of one month when asking respondents whether they are employed, while the 2011-12 NRVA has a recall period of one week. The India NSS includes a weekly status, but it is constructed based on questions about time use over half-days. The yearly status, on the other hand, is identified based on a specific question to the respondent. The Pakistan LFS uses a recall period of one week, but the period is one month in the Pakistan HIES. In Sri Lanka, some of the surveys do not specify a recall period at all when inquiring about employment. The majority of Sri Lanka’s HIESs have information about the usual employment status, while the LFS reports the weekly employment status.

Fourth, the dates when information was collected vary, even within the same type of instrument. For instance, in Afghanistan and India (NSS thin rounds), most of the analyzed surveys did not follow a constant data collection pattern. Another example is the Bangladesh LFS, for which data for the 2002-03 round was collected during a short span (less than six months) while data for the 2005-06 round was collected during a whole year (from October 2005 to September 2006). If there is seasonality in employment, figures from surveys with different data collection periods are not strictly comparable.

In some cases, the dates when information was collected allow generating quarterly employment data, in addition to annual estimates. Censuses are conducted over a very short period of time, and most of the household and labor force surveys record the month when a respondent was interviewed. In these cases, individual observations can be mapped to specific quarters. However, this approach is only used in the case of surveys in which interviews were spread across space and over time in a relatively even way.

Because of these four differences, the way we defined employment varied across countries and sources, as shown in Table 2. We provide even more detailed information in Table A2 in the Appendix, where we report the exact language used in the corresponding questionnaires.

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