Citigroup just became the first major Wall Street bank to name a woman into the top job. Jane Fraser, its president and head of consumer banking, has taken over as chief executive from Mike Corbat, who is set to retire in February. 

The financial sector has a terrible track record in advancing female talent, so Fraser’s appointment represents a milestone for Wall Street banks, which have been pushing their credentials for promoting women into the senior ranks for years, but with few tangible results.