The player ranks in order are as follows.

Intern Ghostbuster
Rookie
Greenhorn
Supernatural Investigator
Novice Ghostbuster
Paranormal Examiner
Slime Collector
Spook Spotter
Spirit Trapper
Ghostbuster
Proton Slinger
Slimer Snagger
Phantom Blaster
Ecto Exterminator
Elite Ghostbuster
Wraith Wrangler
Soul Hunter
Specter Slayer
Defender of New York
Ghostbuster of the Year