Find blank cells, calculate median

Hello,

I have searched all over the forums looking for this without any luck, and I am rather new to macros, so I am hoping someone can help me. Here is my question:

I am trying to find medians for a series of values (in a column) separated by blank rows where the formula knows to end the median calculation when it runs into the first blank cell--and the median number will be calculated in this blank cell.

For instance, cells O3:O15 are filled in, O16 is blank, I want a code that can find the blank O16 cell, and in that cell calculate the median of O3:O15.

I have about 150,000 rows, and there is not a uniform spacing between the blank cell ranges.

thanks in advance!

Beth