I have a macro that draws objects on the worksheet based on data contained in
the cells. In Excel 2003, with a worksheet of 500 lines of data, this macro
ran in about 15 seconds. In 2007, it takes upwards of 15 minutes. As the
macro works down the sheet, the process of drawing my triangles and diamonds
gets slower and slower. It seems like Excel loses processing speed as more
and more objects are drawn on the page.

Is there some way to improve this process?