Weird Excel Problem - Lagging During Scroll

Hi dear all,

i m having a problem in my excel sheet.
its slow on scrolling and even in typing in the letter/decimal into the column.

i have test this on 2 unit of pc.
its way damm slow and lagging even the spreadsheet is blank!!
(i deleted all the data inside)

pls help,thanks very much.

here is my attachment:

http://www.mediafire.com/?iqsr9p671aq5mh9