What's going on: I got nothing when many applicants got rejection from the same grad program

I am an applicant of a biology graduate program. After exploring some on a website, the gradcafe.com, I found that I got nothing when many applicants got rejection on a specific day from the same graduate program. Several waves of invitation were alread gone now, but I got neither invitation nor rejection.

Do you think it's a good sign? I don't know much about how graduate admission process is going on. Could you a bit explain this situation?

PS. I asked about it by an email to the office of the grad program, but they didn't answer yet even after 5 days. No phone number available...