VBA to highlight matching rows and add column to calculate percentage change in unit price

Hi,
Trying to sort through some data and thinking the following will help assist, the original data I'm looking at has around 35,000 rows. Attached is an example, has the column headings of the data. Sorting the data first by Mfr Catalog #, SKU/Catalog #, Amount/UOM & UOM, and PO Date does get the information for the most part so I can see the trend over the years.

What I'm hoping for is that if Mfr Catalog #, Amount/UOM & UOM match the following row then highlight that row A:P (or up to AB), then if that unit price in column N changes (increase/decrease) from the previous to have that percentage change in column AC. If decrease percentage then also highlight cell green, else highlight red.