Switzerland, which promotes equality at home and in the workplace, has been ranked the best country for women's rights, the Organisation for Economic Co-operation and Development (OECD) said in a report on Friday.

Denmark, Sweden, France and Portugal were the next best-performing countries, according to an index that ranked 120 nations on how they tackled discrimination against women through their laws and political reforms.

Meanwhile, Guinea, Jordan, Iran, Pakistan and Yemen came out at the bottom of the OECD's Social Institutions and Gender Index, released to mark International Women's Day.

Gender-based discrimination, including female genital mutilation, reproductive rights, pay gaps, and gender violence, were estimated to cost $6 trillion, or 7.5 percent of the global economy, the report said.

The OECD gave Switzerland a "very low" gender discrimination score of 8.1 out of 100 for having robust laws and social norms that addressed those issues.

Image: OECD

While Yemen had a "very high" score of 64 for its strict gender norms that restricted liberties, financial access, and justice for female victims of violence and rape.

"Despite a global realisation that women's equality is an urgent priority, we are moving too slowly in closing gender gaps, and in some countries gender gaps have even widened," said the OECD's chief of staff, Gabriela Ramos, in a statement.

The gender pay gap sat at 13.6 percent across developed countries, it said.

Women occupy less than a quarter of parliamentary seats globally, the index also said.

"We need to do more and to do it better. We need to be smarter in the way we design and execute policies and be held more accountable on the results. Otherwise we may be looking at another 200 years to achieve gender equality," Ramos said.

Some gains have been made, the report said.

Though one in three women globally still experience domestic violence once in their lifetime, it has become less socially acceptable, it said.

The proportion of women who said domestic violence was acceptable has dropped from 50 percent in 2012 to 27 percent in 2018, the OECD said.

Paid maternity leave is also now guaranteed in every country except Papua New Guinea and the United States, it said.

A report on Tuesday by global accounting firm PwC said increasing the female labour force to match that of Sweden - where 69 percent of women work - would add a further $6 trillion to advanced economies.

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