Two years since Japan made it mandatory for its companies to disclose their gender pay gap, there has been little progress toward equality, with the highest-paying firms showing some of the biggest disparities.

Of Japan’s 100 largest companies by market cap, 70 had disclosed two years’ worth of data that could be analyzed by Bloomberg as of Aug. 15. Only one of them saw a more than 5 percentage point improvement in its gender pay gap.

The government introduced the requirement to reveal pay gaps in 2022, in an effort to support female economic empowerment and entice more women into the workforce as the population shrinks. The data suggest that disclosure alone isn’t enough to change the status quo, and shifts the focus onto other efforts to improve the situation.