Array Variable Sized Boxes

I'm pretty new to grasshopper so you all will have to cut me some slack on my lack of knowledge and terminology.  I've been trying to create a definition which will create a panel that has even division horizontally (let's say 2 or 3 inches) but has variable division vertically in a gradient from top to bottom.  For example the bottom could have more divisions in thinking of it as 90% dense and then the top could have less divisions and be seen as only 10% dense.  It would also be nice if possible to keep the divisions at semi normal lengths (1',2' 4',6' 8', 10').  Icing on the cake would also be figuring out how to add a 2" vertical and horizontal spacing to the array.  

Hopefully this makes sense.  I'm attaching a sketch my boss gave me explaining this idea and a quick illustration diagram of what the desired intent is.  

Thanks in advance!