title: prevent cell reference from iterating when dragging marque down column
body: <p>I have a cell, B2000, with a constant value in it, namely <em>5.25</em>. I reference that value in cell H5 via a function <code>=B2000+G5</code>.</p>
  
  <p>Now I want to highlight cell H5, and then drag the marque down, such that the reference to B2000 will not iterate, but the reference to G5 will iterate down the column.</p>
  
  <p>Is this possible?</p>