One way would be to perform a recalculate at periodic intervals. You can
use the Ontime method to do this
See Chip Pearson's page
http://www.cpearson.com/excel/ontime.htm
--
Regards,
Tom Ogilvy
"engine99" wrote in message
...
I want to reference the cell to do one thing during a period of time and
something else during another period of time.