Employers’ ability to raise wages and other forms of labour income depends on increases in labour productivity, highlighting the welfare implications of productivity growth and its role as a key driver of long-term living standards. Several OECD countries have experienced a slowdown in productivity growth and in real average wage growth. Empirical evidence points to a decline in labour income shares since the mid-1990s in the majority of OECD countries, at least when measured from a producer perspective with gross income as a reference (Cho, 2017[1]). These developments have resulted in a decoupling between labour productivity and real labour income growth (Schwellnus, 2017[2]).
In this chapter, labour productivity is defined as real gross value added per hour worked. Labour share represents the share of total labour compensation in gross value added. Labour income – measured by average labour compensation per hour worked, is adjusted for inflation using the same price index applied to deflate value added (and hence productivity). Real labour productivity growing faster than average hourly real labour compensation (so-called decoupling) will thus lead to a decline in labour share (see more details below in How to read the indicators).
The focus of the chapter is on labour income share developments after excluding primary, real estate, and non-market sector, as developments in those sectors are usually driven by specific factors, such as commodity and asset price developments and national accounting conventions.
The well-being impact of the divergence between average hourly labour income and productivity growth rates is further exacerbated by the widespread slowdown in productivity growth, and in some countries even more so when real labour income is adjusted for inflation using the consumer price index (CPI). Indeed, inflation based on value added or consumer prices can differ significantly, reflecting for instance the effect of terms of trade. Also, the value-added deflator reflects movements in the prices of all goods and services domestically produced, whereas the CPI captures movements in the prices of goods and services in private household consumption only. These can either be imported or domestically produced.
Labour income shares and comparisons between average hourly real labour income and productivity developments in this chapter do not account for labour income inequalities across workers. The majority of OECD countries have experienced a further dissociating between median and average labour income since the mid-1990s, which is related to disproportionate labour income growth at the top of the income distribution (Bivens, 2015[3]) (Schwellnus, 2017[2]).
Despite a large amount of research on the determinants of decoupling, there is no clear consensus on the mechanisms behind it and a number of factors have been put forward. Paternesi, Meloni and Stirati (2023[4]) emphasise that technological progress displaces low-skilled labour in favour of capital and high-skilled labour, which would lead to a deterioration of low-skilled wages, which in turn would not be compensated in the aggregate by rising wages for the skilled group. Karabarbounis and Neiman (2014[5]) argue that the labour share has fallen due to a fall in the price of investment goods. Combined with an elasticity of substitution between labour and capital greater than one, this would lead to capital deepening and a reduction in the labour share. Mishel and Bivens (2021[6]) show that high unemployment, the erosion of collective bargaining, and globalisation are the main factors putting downward pressure on wages in the United States. Stirati and Paternesi Meloni (2021[7])argue that the impact of labour market slack is depressing the private sector labour share in major OECD countries. Guschanski and Onaran (2022[8]) also find that offshoring and changes in labour market institutions are relevant factors in reducing the labour share in some OECD countries. Pro-competition product market regulations and labour market policies (Pak, 2019[9]), as well as changes in the industry composition of the economy (OECD, 2012[10]) can also affect labour shares.