LONDON — Goldman Sachs’ British business on average paid women 51 percent less than men per hour in 2018, the investment bank said Monday, down from 56 percent the year before.

The gap does not reflect the bank paying women at the same level differently from men, the bank said, but rather the fact that fewer women hold the more senior roles that have higher salaries and bonuses.

The data was released as part of rules requiring British firms to regularly disclose their gender pay gaps, and say what measures they are putting in place to try to close the divide.