In most countries, the main source to construct measures of hours actually worked is the labour force survey. However, many countries rely, only or in addition, on establishment surveys and administrative sources. The use of different sources may affect the comparability of labour productivity levels but comparisons of labour productivity growth are less likely to be affected (Ward, Zinni and Marianna, 2018).
Computing estimates of hours worked also implies adjusting the activities covered by the labour input measures (employment and hours worked) to those covered by the output measure. This requires adapting the geographical and economic boundaries of employment and hours worked to the national accounts production boundary, in order to exclude resident persons working in non-resident production units and include non-resident persons working in resident production units.
In practice, countries adopt one of two methods to estimate actual hours worked for productivity analysis:
the direct method, which takes actual hours worked self-reported by respondents in surveys, generally labour force surveys (LFS);
the component method, which starts from contractual, paid or usual hours per week from establishment surveys, administrative sources or the LFS, with subsequent adjustments for absences and overtime, and other adjustments to align hours worked with the concepts of hours actually worked and the concept of domestic output.
While the direct approach appeals due to its simplicity, it depends heavily on respondent recall, cannot account for response bias, and assumes a perfect alignment of measures of workers and output. The component approach is more complex, but it systematically attempts to address these issues. There is evidence that response bias and insufficient adjustments to align with the concept of domestic output led to systematic upward biases in estimates of average hours worked per worker based on the direct approach, as compared to the component approach (Ward, Zinni and Marianna, 2018).
Admittedly, the OECD simplified component method necessarily relies on available data sources. In particular, it assumes that workers in all countries take, on average, all the leave to which they are entitled. However, actual take-up leave rates are likely to reflect differences in working cultures across countries. For this and other reasons, like the access of national statistics offices to a variety of national data sources, the OECD simplified component method estimates should be considered only as a stopgap for those countries currently using a direct approach with minimal or no adjustments, while these countries work towards improving their methodologies (Ward, Zinni, and Marianna, 2018).
Finally, the effective quantity of labour input depends not only on the total number of hours actually worked but also on the education, working experience, business functions and other workers’ characteristics. The measure of labour input used in this publication, i.e. total hours worked, does not account for the composition or “quality” of the workforce and likely underestimates the effective contribution of labour to production.
For further methodological information, consult the OECD Productivity Statistics – Methodological notes at https://www.oecd.org/sdd/productivity-stats/OECD-Productivity-Statistics-Methodological-note.pdf.