So just to be clear...
Class Rank: Top 26% (34/133)
I think my math is on...
Be aware of your school's requirement re: grade and rank reporting too. For instance, my school gives individual rankings only for the top 10% of the class, and then tells people if they're in the top 20%, 25%, 33% (I think), 50%, 75%, etc. You aren't allowed to "compute" your own percentile, and if you do, it's a violation of the honor code (they don't want people making math mistakes or fudging numbers).
So I'd just double check that it's ok to even do your own math before you put it on your resume.
Also, because you're not in the top 25%, I'd just put 34/133, which seems much more impressive than 26%. That's entirely just my opinion though.