Britain’s equality watchdog has warned it will take enforcement action against UK companies who do not publish their gender pay gap. The intiative currently affects only the UK Philip Toscano/PA Wire

With less than two weeks left to file the data, many CEOs will be rushing to crunch the numbers on pay difference at their companies.

Figures on the gender pay gap need to be published on a UK government website by April 4. The date is even earlier - March 30 - for public sector companies.

There are unlimited possible fines at stake, to be levied by the Equal and Human Rights Commission, so it will be important to move quickly on this one.

The EHRC is likely to grant some leeway to smaller companies, and may even help with advice, but larger companies will be expected to get their act in order, and comply, on time.

Thus far, two thirds of the relevant companies (those with more than 250 employees) - some 6,000 - are still to report.

Furthermore, at the time of writing 49 of FTSE100 members, Britain’s biggest companies, are still in this position.

At present, the initiative involves only UK companies but it is likely Isle of Man businesses and government will be watching closely.

Of those that have reported, about 75% have revealed that men earn more money, while at 9% of companies pay is equal, and at 14% of companies women earn more.

It would be intriguing to know what sort of companies these were, if indeed they did fall into any category.

The gender pay gap is different to equal pay. The latter has been illegal for 47 years.

The gender pay gap does not result from companies paying different rates for men and women. It reflects instead differing levels of seniority for the genders. More senior people are male, so they earn higher salaries.

The issue is more complex than it might at first appear.

There is median pay (ie the number slap bang in the middle), and there is mean pay (the figure we would more normally associate with ’average’, but which is affected by big outliers).

There are unadjusted figures, and there are adjusted figures (adjusted for differences in hours worked, occupation chosen, education and job experience). The unadjusted figure is bigger.

Gender pay reporting is no doubt proving inconvenient, not to say embarrassing, for certain companies.

Perhaps unsurprisingly, the biggest differences in gender pay - at 35.6% - occur in the financial and insurance sector. Law firms, with a high proportion of male partners, and travel and aviation companies, with larger numbers of male pilots, also show similar biases. A few weeks ago the insurance company Aviva was first out for the finance sector, announcing a 27.6% median pay gap, putting this down to more males in senior roles.

HSBC also announced high gaps, noting that less than 25% of senior staff are women: these were 29% for median pay (please see definition above), 59% for mean pay, and 86% for bonuses.

As for other finance firms, the gap was 36% at Goldman Sachs and 38% at Virgin Money.

At the Financial Times the median pay gap was 19.4%, and the mean difference 24.4%.

For other media companies the differences were also favourable to men: 12.5% at The Guardian, 17.5% at Sky, 18.2% at ITN, 24.2% at Channel 4, 29.5% at The Economist, and 9.3% at the BBC (perhaps lower than might have been expected given all the publicity in January).

Easyjet (where only 6% of pilots are women) revealed hourly rates 45% less for women, while at Tui the difference was 56.9%.

British American Tobacco has a pay gap of 36%, while at Burberry it was 25.9%. Ladbrokes revealed only a marginal 2.5% difference.

At Cambridge University the difference was reported to be 15%.

There is no doubt that a lot of progress has been made on this matter over the years. As recently as 1997 the gender pay gap was 27.5%, while in April 2017 the aggregate figure had narrowed to 18% (the difference is similar in the United States).

But given what has been reported so far the issue is likely to remain topical.

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