In reply to blue.

yes people quote total weeks of a song but even then they are equal as bey is not credited as a solo act on IW, she only has irreplaceable as rihanna has WFL

and also without their 10weekers
both ladies hardly average 4 weeks per song

so no real difference.

And actually yes, check the charts during rihanna's release dates you will see that she usually releases her albums at a very competitive time and still goes on to outsell those that debut above her, bey's last real competition was xmas albums.