Per Excel help max function should ignore blanks. See below from help.
<TABLE style="WIDTH: 720pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=960><COLGROUP><COL style="WIDTH: 720pt; mso-width-source: userset; mso-width-alt: 35108" width=960><TBODY><TR style="HEIGHT: 15.75pt" height=21><TD style="BORDER-BOTTOM: #f0f0f0; BORDER-LEFT: #f0f0f0; BACKGROUND-COLOR: transparent; WIDTH: 720pt; HEIGHT: 15.75pt; BORDER-TOP: #f0f0f0; BORDER-RIGHT: #f0f0f0" id=td_post_2905308 class=xl65 height=21 width=960>If an argument is an array or reference, only numbers in that array or reference are used. Empty cells, logical values, or text in the array or reference are ignored</TD></TR></TBODY></TABLE>
However this should work if Bst is a single cell.
<TABLE style="WIDTH: 230pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=307><COLGROUP><COL style="WIDTH: 230pt; mso-width-source: userset; mso-width-alt: 11227" width=307><TBODY><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: #f0f0f0; BORDER-LEFT: #f0f0f0; BACKGROUND-COLOR: transparent; WIDTH: 230pt; HEIGHT: 15pt; BORDER-TOP: #f0f0f0; BORDER-RIGHT: #f0f0f0" id=td_post_2905308 height=20 width=307>=MAX(IFERROR(DXP,""))*bst</TD></TR></TBODY></TABLE>
If Bst is a range of values you should be able to use something like this:
<TABLE style="WIDTH: 230pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=307><COLGROUP><COL style="WIDTH: 230pt; mso-width-source: userset; mso-width-alt: 11227" width=307><TBODY><TR style="HEIGHT: 15.75pt" height=21><TD style="BORDER-BOTTOM: #f0f0f0; BORDER-LEFT: #f0f0f0; BACKGROUND-COLOR: transparent; WIDTH: 230pt; HEIGHT: 15.75pt; BORDER-TOP: #f0f0f0; BORDER-RIGHT: #f0f0f0" height=21 width=307></TD></TR></TBODY></TABLE>
=MAX(IFERROR(DXP,""))*MAX(IFERROR(Bst,""))
Both of these are array formulas and must be entered with
CTRL-SHIFT-ENT