First do a timing test to see just how much time is used in
maintaining the formatting. If it's a large enough percentage of the
overall time, consider pre-formatting your destination sheet.
To reduce the overall time of the process, precede the data collection
loop with Application.ScreenUpdating = False
Then after all the collection and pasting of data turn on
ScreenUpdating.
You could time the process with and without ScreenUpdating turned on
and with and without maintaining the cell formatting, just to identify
the time-intensive portion of your macro.

jmac