EARLY IN DECEMBER, we asked if you had any nagging questions remaining from 2016, about claims or facts or statistics you heard again and again over the course of the past 12 months.

We were inundated with excellent suggestions from readers, and picked out the very best ones. For the second installment, we’re looking at the gender pay gap.

Neil Mac Dhonnagáin had seen a lot of coverage and claims about this issue over the past year, and got in touch with us on Twitter to ask us to clear things up.

The Facts

The “gender pay gap” is the difference between what women and men earn, on average, per hour, before tax.

The most recent commonly cited official figure is 14.41%, taken from 2014 data from Eurostat, the European Commission’s statistics agency.

This means that on average, women earn 14.41% less than men, per hour.

One of the most common claims around the gender pay gap is that this unequal pay is “for the same work“, with the strong implication being that women are paid less on the specific basis of their gender.

But this is not the case, generally speaking. Of course, there may be instances where women are paid less for doing the same work and the same hours as a male counterpart.

But such behaviour is gender-based discrimination, and is illegal under the Employment Equality Act.

The gender pay gap is a reality, but it’s not what it’s often portrayed as. So let’s take a deeper look at the data, to see what’s at play here.

“Gender overall earnings gap”

Source: Shutterstock/ibreakstock

This is the difference between what men and women make in a month, on average, before tax. Believe it or not, the meaning of “on average” here is important.

The best source of figures on this is Eurostat’s “Structure of Earnings Survey”, which takes place every four years, the most recent one being in 2014.

It offers the mean and median monthly earnings of male and female employees in a variety of types of position, in part-time or full-time roles, and in various age brackets.

The mean is simply the total paid out divided by the number of workers, whereas the median is the monthly pay that half of workers earn above, and half earn below.

It is often regarded as a more reliable reflection of the average than the mean, because it’s not skewed by extremely high or low numbers, so we’ll be looking primarily at that, but you can check out the mean as well in a spreadsheet you can download below.

First, here are the figures for total monthly wages:

Source: For a full-size version of this chart, click here

So women, on average, earn 22.8% less than men each month. But here’s something important that you should know – women, on average, work fewer hours each month than men – 129 as opposed to 149.

So when we adjust for that difference, and calculate hourly pay, let’s see what happens:

Source: For a full-size version of this chart, click here

The gender gap shrinks, from 22.8% for monthly pay to 10.9% for hourly pay, when you take into account the fact that women, on average, work fewer hours than men.

Incidentally, the mean hourly wage gap (not median) is 14.4%, which is where the commonly-cited figure of 14% comes from.

So let’s look at various different categories, comparing the monthly gap to the hourly gap.

Full-time vs part-time

Source: For a full-size version of this chart, click here

So while male full-time workers earn 10.6% more, on average, than their female counterparts, that gap rises to 14% when it comes to part-time work.

When you take the mean figures, the gap is 15.9% for full-time workers, and 10.8% for part-time workers.

Source: For a full-size version of this chart, click here

And when hours worked are taken into account, the gap for full-time workers shrinks from 10.6% to 6%, but stays at 14% when it comes to part-time workers, because men and women in these roles both work an average of 87 hours a month.

Type of position

Source: For a full-size version of this chart, click here

As you can see, the monthly wage gap is significant in every category, ranging from 8.6% for “plant and machine operators“, to 38.7% for “elementary occupations“, which include lower-paid jobs like domestic cleaners, street vendors, agricultural labourers and freight handlers.

(You can find a description of each of the types of position mentioned, here).

Source: For a full-size version of this chart, click here

When we account for hours worked, the gender pay gap shrinks significantly in almost every category, but remains 9.2% at its very lowest and 23.6% at its highest, for clerical support workers.

Interestingly, female plant and machine operators actually work more hours per month, on average, than their male counterparts (161 as opposed to 160), so when that’s taken into account the gender gap actually grows, from 8.6% for monthly wages to 9.2% for hourly wages.

Age

Source: For a full-size version of this chart, click here

What’s most striking about this is the way monthly wages grow for men over the years, and sustain that growth, as opposed to women.

While the gender gap in monthly wages is only 12% and 12.6% for workers aged up to 39, it explodes to 27.9% in the 40s, and reaches 41.4% for those aged over 60.

And while monthly wages reach a peak of €3,754 for men in their 50s, women will, on average, never earn as much as they do in their 30s (€2,682 per month).

Similarly, while a man in his 60s earns significantly more than a man aged under 30 (€3,034 vs €2,166), a woman in her 60s earns less than a woman aged under 30 (€1,777 vs €1,907).

Source: For a full-size version of this chart, click here

As you might have expected, the number of hours worked has an impact here, again, with men consistently working more hours per month than women, causing the gender gap to shrink across all age groups, when compared to monthly wages.

What stands out from these figures is that women aged under 40 earn almost as much as their male counterparts, with the hourly wage gap standing at just 2.6% for those under 30, and 1.4% for those in their 30s.

However, when we take the mean figures (rather than the median), the gap is 1.1% for men and women under 30, and 6.2% for men and women aged 30-39.

So while there may or may not be an expansion of the gap in the 30s, depending on your method of calculation, we know that the discrepancy in pay between men and women is very significantly lower for workers under 40, than it is for all other age groups.

A “motherhood gap”?

One theory that could partly explain this phenomenon is the “motherhood gap” or “motherhood penalty”, which appears to show that a woman’s career progress is interrupted by having children.

Maternity leave can create gaps in employment, disrupt what may have been a path toward promotions and pay raises, and women returning from maternity leave might take up the same role they had previously, or return on a part-time basis, all factors contributing to lower pay than male counterparts.

Furthermore, by choice or otherwise, women also often seek or require greater flexibility in working hours than their male counterparts, for reasons of family and in particular, child care.

With men comparatively free to dedicate a greater number of hours – and in particular, anti-social hours, including travel for work – they often progress more quickly along the path towards promotion.

The “motherhood gap” is often understood to kick in during a woman’s 30s, which is roughly the average age at which a woman has her first child (in Ireland, the median was 30.1 years in 2014, according to our analysis of CSO data.

However, this theory would appear to be confounded by the data showing that the hourly gender gap actually shrinks, rather than grows, from 2.6% for those under 30 to 1.4% for those in their 30s (when the median hourly wage is used).

But this further complicated by the fact that the gap does expand (from 1.1% to 6.2%) when the mean hourly wage is used.

Conclusion

Source: Shutterstock/Syda Productions

This is a complex issue, which will require further research and more detailed data, in the coming years.

But we can dispell a couple of myths, at this stage.

Firstly, the gender pay gap isn’t really about discrimination. In the relatively rare cases where it is, an employer is breaking the law.

Women don’t earn less than men simply by virtue of being women. The causes are complex, and often strongly related to a woman’s gender, but gender is not in itself the cause, generally speaking.

Equally though, the gender pay gap is a real phenomenon, contrary to the commonly-expressed view that it is a “myth” (this is, itself, a kind of myth).

Even when you account for the greater number of hours that men work, on average the hourly wages of women are less than those of men – across various types of job, whether part-time or full-time, and across all age groups.

It is real, and pervasive. But it’s not uniformly pervasive. As this article has shown, age in particular matters a great deal, with younger women earning almost as much as younger men, while the gender gap stretches to between 20% and 30% for women in their 50s and 60s.

For certain occupations (particularly the very low-paid types of jobs included in “elementary occupations” in the Eurostat data), the gap is desperately wide, with women earning almost one quarter less than their men.

On the other hand, women who work full time earn, by comparison, only 6% less than men who work full time.

To download a spreadsheet containing all the relevant data, click here.

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