How Does the Gender Wage Gap Vary Over the Life Course and Across Cohorts?

Nearly half a century after Britain's Equal Pay Act the convergence of men's and women's pay is slow and incomplete. Although the trend in the gender wage gap (GWG) is towards convergence, for any given birth cohort the GWG rises as people age from their twenties to mid-life, growing upon family formation. Thus, explanations of the GWG tend to focus on the time women spend away from paid work after childbirth and the difficulties they face in establishing their previous pay level on returning to the labour market. Pay penalties are particularly pronounced for women returning to part-time employment. Some people maintain that these patterns reflect women's preferences for work-life balance and conventional norms about the division of domestic labour, while others point to discriminatory practices in the workplace.

By analysing nationally representative cohort data for people born in Britain in 1958, 1970 and 1989/90 this study addresses three gaps in knowledge. First, evidence will be extended to wages and employment at later ages than has been studied hitherto. Second, it will be extended backwards to explore linkages from childhood years to labour market experience, making innovative use of under-utilised material including biometric indicators. Third, we will be able to distinguish between the effects of ageing and of having been born male or female at different points in history. This is something that is only possible with data tracking more than one cohort. There are three reasons to anticipate cohort effects:
(i) People born at different times are exposed to different labour market and policy conditions during their lifetimes. For instance, the 1958 cohort left school when the Equal Pay and other Equal Opportunities provisions were first being implemented whereas these had been in place for a decade when the 1970 cohort finished school.
(ii) The education gap between men and women has disappeared and even reversed, such that the pay-off due to qualifications will have shifted markedly between men and women across the generations.
(iii) Attitudes to women's participation in the labour market and to men's in domestic labour have shifted. These changes in social norms, together with attendant changes in public policy, have created opportunities for men and women to combine paid work, parenthood and leisure in ways not hitherto possible, with uncertain consequences for the life choices and earnings patterns of men and women across the life course.

The study will address five related questions:
1. What does the GWG look like over the life course and across birth cohorts? Does it change later in life and how does it compare across cohorts for people at the same points in their life?
2. How much of the GWG is accounted for by differences in human capital (qualifications and work experience) accumulated over the life course? How different does the course of the wage gap look across ages for men and women with similar human capital attributes?
3. What role do parenthood and caring responsibilities play in the emergence of differences between men and women in employment and pay and how the GWG persists over the life-course?
4. How much of the GWG is attributable to the sorts of jobs undertaken by men and women, particularly in respect of occupation and part-time hours?
5. What role do childhood attributes and experiences play in determining the subsequent GWG and do childhood influences still matter having accounted for early adulthood experiences?
The study will provide a comprehensive anatomy of the GWG across individuals' life-times, up to the age of 61 in the case of the 1958 cohort, and across three generations with births spanning 40 years, offering numerous insights into wage formation which will assist in efforts to mitigate the consequences of unequal treatment in the past and promote gender equality in the present and future.

This project will inform policy on women's pay relative to men's, and the factors that determine any discrepancy. It is timely given the new requirements for large organisations to report their gender wage gaps. We will examine changes in the gap across the life-cycle and across cohorts, offering insights into a range of policy-related issues. First and foremost, it will provide a clear and robust set of estimates regarding the evolution of the gender pay gap five decades after the passage of the Equal Pay Act. Policy-makers will be able to benchmark progress that has been made towards gender equality whilst variance in that gap across sub-groups of the population (eg. by education level and social class) will help inform where policy makers should focus their efforts in future. Regression analyses will introduce potential determinants of the gender wage gap in a step-wise fashion to help account for the size of the gap. In doing so, it will quantify the importance of various factors, again helping policy-makers focus their efforts on factors that appear to account for most of the variance. Similar analyses will be undertaken for different parts of the earnings distribution, thus going beyond the usual focus on differences in mean earnings. Estimating gender gaps in different parts of the wage distribution will help in analysing any impact of existing policies which "bite" at different points, such as the national minimum wage.

All government departments should find our results useful because they are now all under a statutory duty to monitor and report on equality among their own departmental employees. Public sector bodies also have a statutory duty to eliminate discrimination and advance equality of opportunity. But the government agencies who are most likely to benefit from this knowledge about the size and sources of the gender wage gap are those with direct responsibility for the promotion and enforcement of equal treatment across the workforce, including the Government Equalities Office, the Department for International Development (its Secretary of State is currently Minister for Women and Equalities), the Equality and Human Rights Commission, the Low Pay Commission, the Department for Business, Energy and Industrial Strategy (responsible for issues such as flexible working and parental leave), Acas (who provide guidance on equal pay), and the Department for Work and Pensions (responsible for pension policy). Beyond the UK, researchers in the OECD and the European Commission will want to know what the implications of the study are for policy formation internationally.

Women's groups and those promoting women's rights, such as the Women's Equality Party and the Women's Budget Group, can refer to our evidence on potential discrimination against women at work, in terms of recruitment, pay and progression. Evidence of changes in the size of the gender wage gap over the life-course will be of interest to groups lobbying on their behalf, such as Age Concern who are interested in older workers and pensions, while Mumsnet may focus on findings about family formation.

Trade unions seek to promote equality at work and eliminate employer discriminatory behaviour. They have a special interest in gender equality with women now constituting the majority of union members. They will examine our research to further their understanding of what lies behind the gender wage gap and use the evidence to promote further government and societal action to eliminate it. As the professional body for personnel managers, the Chartered Institute for Personnel Development will look to the study to help promote and encourage gender equality at work.

The one day workshop will bring together these practitioner and policy beneficiaries with academics in the field to discuss early findings from the study and their implications for policy and practice which will be reflected in our policy report.