Inconsistent Data in NRC Rankings

[chaospaladin]

I was looking at the NRC rankings on Phd.org for ecology just for fun and I came across this:

http://graduate-scho...____________U/3

For University of Toledo, how is it possible that the average length to a PhD is 4 years yet 0% of PhD students get their PhD in Ecology at University of Toledo within 6 years or fewer? Is there something I'm missing? I also encountered these inconsistencies for other fields listed.

[eco_env]

I think it's because it's a small dataset- no one graduated in the particular years where data was collected. Also, the time to graduation probably ignores people who drop out, while they are probably counted in the graduation rate.