Are actors or actresses more crucial to best picture noms?

Right now, I'm just enjoying that a decade has concluded and it's sort of ripe for analysis. It's kind of like a statistician in a room full of data.
For instance, I had this theory as I was making a best actors list that they're much more important than best actresses because they fuel a best picture nomination much more often.

I took the top 15 actresses of the last decade according to my last list. These actresses are Kidman, Blanchett, Streep, Winslet, Zellweger, Whitherspoon, Dench, Scarlett Johannson, Julia Roberts, Juliane Moore, Naiomi Watts, Helen Mirren, Jennifer Connelly, Kiera Knightly, and Charlize Theron. I made that list objectively without

I am working on a list of top actors and I was planning on excluding Daniel Day-Lewis because he hasn't appeared in a minimum # of pictures for comparison, but nonetheless, I have something along the lines of DiCaprio, Crowe, Depp, Penn, Damon, Pitt, Clooney, Denzel, Cruise, Hanks, PS Hoffman, Jamie Foxx, Heath Ledger, Daniel Day-Lewis and Joaquin Pheonix.

Let's look at how each group of 15 actors has appeared in all 55 nominated films of the last decade:
Guys:
1. Chocolat-Depp, 2. Gladiator-Crowe/Pheonix 3. A Beautiful Mind-Crowe 4. Gangs of New York-DiCaprio/Day-Lewis 5. Mystic River-Penn 6. Master and Commander-Crowe 7. Ray-Foxx 8. Finding Neverland-Depp 9. Aviator-DiCaprio 10. Capote-Hoffman 11. Brokeback Mountain-Ledger 12. Good Night and Good Luck-Clooney 13. Babel-Pitt 14. Departed-Damon/DiCaprio 15. There Will be Blood-Day-Lewis 16. Michael Clayton-Clooney 17. Benjamin Buttons-Pitt 18. Milk-Penn 19. Inglorious Basterds-Pitt 20. Up in the Air-Clooney
Gals:
1. Erin Brockovitch-Roberts 2. Chocolat-Dench 3. Beautiful Mind-Connelly 4. Moulan Rouge-Kidman 5. Chicago-Zellweger 6. The Hours-Kidman/Moore/Streep 7. LOTR: Fellowship of the Ring-Blanchett 8. LOTR: Two Towers-Blanchett 9. LOTR: Return of the King-Blanchett 10. Lost in Translation-Johannsen 11. Aviator-Blanchett 12. Finding Neverland-Winslet 13. Babel-Blanchett 14. The Queen-Mirren 15. Atonement-Knightly 16. Reader-Winslet 17. Buttons-Blanchett


In the end, it's not that far of a difference.

Except if I were to only award a half a point for supporting performances that don't really lead the film: You have Blanchett in all 3 Lord of the Rings films, Blanchett in the Aviator, Blanchett in Benjamin Buttons, Winslet in Finding Neverland, Dench in Chocolat compared to Clooney for Good Night and Good Luck so that's something to consider. Even when someone like Brad Pitt in Inglorious Basterds is a supporting role, he's marketed heavily as the lead as we saw with the recent promotion for that film.