Last week saw the passage of The Fawcett Society’s Equal Pay Day. By the charity’s calculations based on average earnings, from November 22 through to the end of this year women in the UK are “working for free” because of the gender pay gap.

It’s been 48 years since the Equal Pay Act came into force and despite an array of initiatives, government decrees, mentoring schemes and networking programmes, gender parity remains a challenge in the world of work. Yes, things have improved, but not enough and not at anything that could remotely be described as “at pace”.

According to The Fawcett Society, working women in the UK take home on average £574 less per month than men, which comes to £6,888 per year. The group says a lack of flexible working in well-paid, high-quality jobs has forced women to put up with less fair and equal working arrangements in exchange for the ability to juggle the family care commitments which they tend to shoulder to a far greater extent than men.

This in one part of a complex network of interlocking factors that contribute to gender-based inequality stemming from societal pressures and unconscious bias through to outright misogyny. The latter is in the diminishing minority, but the former have proven perniciously resistant to extermination efforts.

When it comes to the raw numbers on earnings, one of the biggest factors that keeps women’s average pay below that of men is a relative lack of females advancing to the upper end of the management hierarchy.

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Research from the latest Women Count report released yesterday suggests that the UK’s biggest listed companies continue to struggle with blind spots and operate at “various levels of consciousness” when it comes to senior female staff. This year’s report found that the percentage of women in executive committee roles in the FTSE 350 has broken through 30% for the first time, but the ratio falls to just one in five of all commercial roles, defined as those with responsibility for profit and loss-making activities.

This is significant because companies prefer a chief executive with experience of running a business unit. Women at board level are more likely to hold “functional” positions such as those in human resources or marketing.

“One of the conclusions that is inescapable from the data shared in the report is that women count, but men count more,” Create Fertility founder and chief executive Geeta Nargund says in her introduction.

“The statistics speak for themselves and show us that whilst there is progress, much more needs to be done if UK business is to achieve gender parity not just in boardrooms, but in the breadth of executive leadership teams.”

The corporate boardrooms of the world’s largest companies hold enormous influence and have more financial power than governments of many developing countries. A lack of female leadership in this focal point of the private sector is detrimental to wider efforts to reduce gender inequality and close the wage gap across all levels of income.

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The Women Count report from The Pipeline, a business championing executive women, found that many UK companies are failing to address important barriers faced by female employees. Among these is the “woman tax”, whereby women are given additional tasks alongside their day job which are not given to their male peers.

And while more women are at the boardroom table, very few are in the driving seat. Just 13% of London’s 100 largest listed companies has a female chief executive – hardly a beacon of excellence – with that number falling to 9% among the FTSE 350.

The report also found sharp variations between different sectors. Industries such as health, insurance, transport and utilities are moving towards gender parity with women in more than 40% of executive leadership roles, but others such as automobiles and mining are at less than 10%.

One sector, private equity, has no female representation at all. Perhaps this goes some way towards explaining why, according to a recent report from the British Business Bank, there has been no improvement in the share of venture capital investment received by female founders during the past decade with that figure stuck at just 2%.

The rate of progress is cause for concern, and the next phase of breaking into the very top roles will likely take even longer.

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FTSE Women Leaders Review, the latest government-backed campaign group working to get more women into the executive suite, has now set its sights on ensuring that every FTSE 350 company has a woman in at least one of the “big four” posts of chair, chief executive, finance director or senior independent director by the end of next year. Among the FTSE 100, 19% currently do not meet this target, rising to 36% in the FTSE 250 and 41% across the FTSE All-Share (ex-350).

Gender diversity programmes helped along by three consecutive government-backed schemes have pushed the proportion of women holding boardroom positions across the FTSE 350 from 9.5% in 2011 to 40.2% earlier this year. This came three years ahead of schedule but a great deal of this achievement is attributable to the rise in appointments of non-executive directors, which is not sufficient to impact the executive pipeline.

Sue O’Brien, chair of The Pipeline, says overall progress has been “glacial”.

“Businesses must not shy away from some of these uncomfortable truths,” she added.

“Leaders need to examine their workplace culture and ensure that their promotion procedures are truly equitable as well as being merit-based. Taking care of, developing and investing in the workforce you already have is a priority.”