Hi,
Please try to give useful informations.
* I can't find information about voltage drop in post#1.
* Now we know that you are concerned about voltage drop. But we don't know how much (maybe I just didn't find it?)
--> A bit of voltage drop is quite expectable.
But "no load voltage" often is not useful. Most voltage regulators are specified with "minimum load". I recommend to use at least 5mA of minimum load (1 kOhm) to get comparable measurement results.
***
I see you used a breadboard. This is not useful because you usually cant fulfill layout considerations with a breadboard. Did you read and keep on "PCB LAYOUT GUIDE" section of the datasheet? It is essential for proper operation.
Klaus