what are the real rankings here?

Kappa/Tri delt/Chi O
Theta
Pi phi
Gama Phi
Alpha Chi
DG
Alpha phi
AOpi
AGD

The ranks by RealRanking are from many years ago. Many many years ago. The current (after fall recruitment) rankings are as follow:

Theta/Kappa
Tri Delta
Gamma Phi
Pi Phi
Chi O
DG/AXO
AP
AOII
AGD

The comment above is almost correct - just a couple of houses need changing:

Theta/Tri Delta
Kappa
Gamma Phi
Pi Phi
Chi O
DG/AP
AXO
AOII
AGD

How do you come up with this ranking?

Theta
Kappa
Tri Delta
Pi Phi
Chi O
Gamma Phi
DG
AP
AXO
AOII
AGD

The person ranking above is a Pi Phi determined to use this site to raise their rankings. The true rankings are:

Theta/Kappa
Tri Delta
Gamma Phi
Chi O
Pi Phi
DG/AXO
AP
AOII
AGD

Theta
Tri Delt/Kappa
Gamma Phi/Chi O
Pi Phi/DG/AXO/AP
AOII/AGD

Theta
Tri Delt
Kappa
Gamma Phi
Pi Phi / Chi O
AXO / DG
AP / AOII
AGD

Okay, so these rankings are made by people who are absolutely delusional. The lists above were the true rankings several years ago, but there have been a number of huge shifts in Panhellenic whether certain houses want to admit it or not.

Tri Delta: These girls continuously place in campus events such as u-sing, homecoming, and scandals, are successful with their philanthropies, and are generally well liked. Their hard work has paid off and they rushed number one last year. I wouldn't be surprised if they did the same this year as well.
Kappa Kappa Gamma: Another house who's consistently strong. They're similar to Tri Delta in that they have good grades, good girls, and good campus involvement.
Chi Omega: They've fallen somewhat over the years, but recently they've made a solid comeback. They rushed really well both last year and this year and got two really amazing pledge classes.
Kappa Alpha Theta: Although still a solid top tier house, KAO has fallen substantially since my freshman year. The past three pledge classes have been getting worse and worse, and the girls in this house are extremely divided. That being said, they still have some of the best philanthropies on campus.
Pi Beta Phi: Several scandals have led Pi Phi to the bottom of the top. However, the girls in this house are genuinely sweet and have a great sisterhood.
Delta Gamma: This house marks the beginning of the middle tier. However, word on the street is that they might be leaving campus next year(cont)

Delta Gamma (Cont): which would be a shame because the girls in this house have been working incredibly hard to boostt their house's status. Anchorman is one of my favorite events each year.
Alpha Phi: This house only returned to campus six or so years ago, and have moved up an INCREDIBLE amount. AOII came back on campus 11 years ago and are still at the bottom, but Alpha Phi's most recent pledge class has solidified them as upper middle. However, there are several girls in this house who party way too hard and from what I've heard the house is divided.
Gamma Phi Beta: A really good house, but I haven't seen much from them since I came to OU. They're consistently good, but are very much in the background of OU greek life. Some people call them "Grandma Phi Beta" because of their reputation as 'snoozers', but the girls i know in this house are fun, involved, and really sweet.
Alpha Chi Omega: These are the party girls, and they've been dropping for a while. There are some really cool, laid back girls in AXO, but as a whole they have a bad reputation.
Alpha Omicron Pi: The girls in this house are very artsy. They have an amazing sisterhood though, and some of the happiest sorority girls I know have been a member of AOII.
Alpha Gamma Delta: By far the nicest girls on campus. They have a negative reputation, but they are laid back enough about it to not care. The AGDs I've met are proud of their house and their sisters, and I don't think they deserve all the crap they get.