well I am not very familiar with this type of voltage regulator at all, so I did a quick google search and came up with the following
the following is an excerpt from this PDF http://www-personal.engin.umd.umich.edu/~fmeral/ELECTRONICS%20I/0300%20Linear%20Volt-Reg/0300%20Linear%20Volt-Reg.pdfpersonal.engin.umd.umich.edu/~fmeral/ELECTRONICS%20I
/0300%20Linear%20Volt-Reg/0300%20Linear%20Volt-Reg.pdf
Based on the first paragraph there I would need to load current to find Vout. correct?