Energy giant Shell has revealed it pays women 22.2% less on average than its male staff, according to its gender pay gap report.

Shell said this is because it has fewer women in technical and senior roles, where pay is higher. The company said that globally, around 20% of roles were held by women, with only 25% of graduates in science, technology and mathematics made up by women, and 14% for engineering and technology.

The company said it was, however, improving representation. It said between 2005 and 2017, women in senior management roles had risen from 12% to 26.8%, while 47% of all graduates are now female.

Shell reached its pay gap figure by calculating the average hourly pay rate for male and female employees.

Shell UK country chair, Sinead Lynch, said: “Equal pay ensures men and women are paid equally for work of equal value. Through our robust and non-discriminatory pay processes, we are confident we have equal pay, however, we do have a gender pay gap.

“Across all our employees in the UK, that pay gap is 22.2%. This means our average hourly rate for all our female employees is 22.2% lower than the average hourly rate for all our male employees.”

Ronan Cassidy, chief HR and corporate officer, said the pay gap report formed an “opportunity to take stock” while providing a reminder to maintain a focus on the issue.

“Our drive to gender balance started years ago,” he said. “Are we where we aspire to be? No. But we should recognise the significant progress we have made, especially the marked change in gender balance at recruitment and the increase in senior leadership representation, and draw confidence from that for the future in driving gender representation towards critical mass.

“The executive committee and I remain passionately committed to improving gender balance across all our businesses.”