conditional concatenation

Hello,

I'm really new to VBA and need some help with the following:

I have a worksheet that starts with Original Value, Start, End, and I need to generate the New Value.

Hello,

I'm really new to VBA and need some help with the following:

I have a worksheet that starts with Original Value, Start, End, and I need to generate the New Value.

I have attached an example of the data.

New Value explanation:
A & B are concatenated because they have the same start date and they have not reached their end date.
A, B, C are concatenated because C's Start <> B's Start and they have not reached an End.
A is dropped because D's start is >= to A's End.
There could be hundreds of rows of data to concatenate depending on their start and end dates.

I posted this question here as well: http://www.mrexcel.com/forum/showthread.php?t=490757

Thanks in advance for any help you can give me, I'm getting desperate.