The share of women among Japan's lawmakers was 15.7% as of last December, the lowest among the Group of Seven leading industrialized nations, an Inter-Parliamentary Union report said Thursday.
The global average was 27.2%.
"Our work is far from done as we aim for gender parity," said an official from the Geneva-based global organization of national parliaments.
The global average improved from 11.3% in 1995, but the growth has been sluggish in recent years.
In the world's 73 parliaments that held elections in 2024, the share of female lawmakers increased just 1.4 percentage points after the elections.
In the rankings of the unicameral parliaments or the lower houses of bicameral assemblies, Rwanda held the top slot at 63.8%, followed by Cuba's 55.7% and Nicaragua's 55.0%.
Six countries exceeded 50%. Many have a quota system allocating a certain percentage of parliamentary seats to women.
Japan ranked 130th among 167 countries whose results can be compared with those in 1995. Its growth in the past 30 years was 13.0 points, 103rd among those surveyed.
The report "shows that the gender glass ceiling in parliaments has cracked but is far from shattered," IPU Secretary-General Martin Chungong said in a statement. "There has been progress but the backlash against women's rights in some countries is extremely worrying."
The IPU released the report to mark the 30 years since the fourth meeting of the World Conference on Women in September 1995, which adopted the Beijing declaration, a landmark U.N. framework showing a road map for gender equality and women's rights. The first meeting was held in 1975, the year when March 8 was designated as International Women's Day.
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