[ubernostrum]

What else would be a better indicator of math competency than math tests?

Have you investigated why there's a difference? Your comments seem to be leaning toward dismissing this problem as not in need of an explanation, but the explanation matters a great deal. Do you believe those scores could be changed by changing educational approaches? Do you believe there's something genetically innate causing the lower scores? Do you believe there's some social factor or combination of factors which could be changed?

You don't get to just say "oh, score gap, question answered".