I am calculating the operating efficiency of companies in a Custom Factor as shown in the attached notebook. Next, I would like to get the top 50% of the assets by this value from the default_us_equity_universe_mask() universe. So, I am using:
universe = Efficiency(mask = default_us_equity_universe_mask()).percentile_between(50, 100)
But this is returning 0 assets, even though the Efficiency has values for these assets.
What should I do to correct this?