Ride-hailing app Uber, under the microscope due to a handful of driver assaults on passengers in some cities, pledged in a blog post to sign up one million female drivers globally by 2020. The ride service did not provide comparable figures for how many women drivers are on the Uber service globally today. “Uber does not require (minimum) hours, and it does not require a schedule,” said Salle Yoo, Uber’s general counsel, in an interview Monday about why women might find working for Uber attractive.