Today is "Equal Pay Day", the date which marks the number of extra days the average woman has to work in a year to earn as much as a male counterpart.
Shockingly, the gender pay gap is actually getting worse, with women effectively working three days more for free than they were last year. In fact, campaigners say that women working full-time still earn £5,200 (15.7%) less per year on average than their male colleagues.
Frances O'Grady, general secretary of the Trade Union Congress, said: “It feels like the glass ceiling is getting stronger not weaker and we need a much tougher approach to stop future generations of women from suffering this pay penalty."
Here are nine shocking facts that underline how women still need equal pay.
Dr Eva Neitzert, deputy chief executive of the Fawcett Society campaign group, said: "It is disgraceful that in 2014 women in the UK still effectively work for free for nearly two months of the year relative to men and deeply concerning that last year the gap widened again for the first time in five years.
"The UK is fast sliding down the rankings of gender equal societies and we need to take action now. We urgently need action to tackle low pay, with the majority of those paid below the Living Wage female.
"Our research shows that lifting the national minimum wage to the Living Wage would reduce the gap by 0.8% - this compares to a historic slow pace of change that has seen the gap fall by just 6.2% over the past 16 years.
"We also need to make sure that having children does not spell the end of a woman's career progression by ensuring that part-time and flexible work opportunities are available at more senior levels. The public sector should lead by example and advertise all vacancies on a flexible basis, unless there is a clear business case not to."
Gloria De Piero, Labour's shadow minister for women and equalities, said: "Women are working an extra three days for free this year because the pay gap is back on the rise.
"Women shouldn't have to wait another 50 years for equal pay which is why Labour will be calling a vote in Parliament to get big companies to publish their pay gap. If David Cameron's Government doesn't act, a Labour government will."
A Government spokesperson said: “The government is committed to delivering a long-term economic plan that works for everyone. Under this government there are more women employed in the UK than ever before and we are pleased that the overall trend on the gender pay gap continues downwards. The gap for full-time workers under 40 is now almost zero and it continues to narrow for the over 40s.
“However, it remains too high and we are committed to reducing it more. That’s why we are giving employees the right to request flexible working, introducing Tax Free Childcare and shared parental leave from 2015 to make it easier for women to balance work and families.”