EARLIER this week, thousands of firms were rushing to meet the deadline for publishing their gender pay gap figures. The final numbers suggested 78 per cent of companies pay men more than women, with the gaps in some cases reaching 60 to 70 per cent. Those kind of figures have quite rightly led to anger and frustration. But has it always been targeted in the right direction?

The obvious problem with the figures is the one that always emerges with league tables based on bald statistics: they do not necessarily expose the deeper problems underneath. The pay gap is huge across the British workforce, but average salaries do not reflect the details of the jobs that people are doing. Gender pay disparity goes far deeper.

Much of the problem is caused by the “leaky pipeline”, an apt little phrase that describes the process by which the gender balance that often exists in the lower levels of a profession leaks away as you head up to senior positions at the top. The result is that men are clustered at the top, where pay is higher, while women are disproportionately represented in the lower-paid, and often part-time, jobs in the middle and lower levels.

Nowhere is this more obvious than at Ryanair, where there are relatively few female pilots and the pay gap was the worst recorded - 72 per cent. But the phenomenon of men dominating senior roles can be seen elsewhere, perhaps most surprisingly in universities. New figures published in The Herald today show that male professors overwhelmingly hold senior academic roles at Scottish universities and in two-thirds of universities less than a quarter of top academic staff are women. Some institutions have no female professors at all.

The explanation lies with a number of factors, some of which are particular to universities while others apply to wider society. The problem on campuses is that the environment is still not conducive to helping women make the same kind of career progress that men do. There are the long hours; then there’s the pressure to publish and the need to balance teaching and research, all of which can be incompatible with family and caring responsibilities.

In addition, we still have not – even after all these years – cracked two of the major issues that lead to women being under-represented in senior roles: the lack of good, affordable child care and the culture in the British workplace that under-values part-time work.

On child care, most of the problem is cost, with a recent Scottish Government report suggesting that more than two-thirds of parents are struggling to pay for pre-school care. The Government’s tax-free childcare scheme is a significant step in the right direction, but the entitlement for parents of three and four-year-olds is capped at 16 hours a week, and only 35 per cent of Scottish parents claim their allowance.

As for the issue of part-time work, it is still the case that women are more likely to do it and that their long-term career prospects will suffer as a result. Universities, for example, still offer very few part-time professorships; our execrable paternity pay – and some pretty persistent gender stereotypes - also make it much harder for men to go part-time or take a career break to care for children.

All of these factors contribute to the so-called leaky pipeline and by extension the gender pay gap. The gap is not generally about people doing the same job - paying men and women differently for doing the same, or equivalent, jobs is illegal. Rather it is about the profound and persistent cultural, social and economic expectations and pressures that produce a gender gap that widens the further up the career ladder you go. Fixing that problem is the only long-term way to rebalance the disparity in pay, but we still have a long, long way to go.