Microsoft Excel - Auto increment + Numbering of grouped cells

Hi
We know that :
If I have a sheet that I want to increment the numbers on the cells so i will use Auto increment next cell by dragging the bottom right corner of the cell.

in the file attached, temp1.zip 

On sheet1 of temp1.xls if we click on 3rd level(encircled in red in the diagram below), we can see pink lines.


now lets number the pink lines 1,2,3 and so on..

if i insert another pink line , then ill have to re-number all the pink lines.
Is there a function which will help me re-number the pink colured cells easily and quickly??

Note: Pink coloured lines are nothin but grouping of cells.


Please help.

Thanks,
Ashfaque

Check out your other post. You dont need to multi-post here.

Hi ,

Am sorry i made a mistake in showing the output:

For Case1, Before case2 starts the numbering should be in continuity, as shown below:

 

Please help.
Thanks
Ashfaque

Refer your other post