Need to track and display a "Best Day" value based on category

[RBumgarner]

What I need to do is to keep track of the max value based on a category.

To elaborate:
We make 12 different products.
We can make any number of each on any given day.
My list sheet is arranged by date, category, pounds produced, and a number of other data ranges. (several thousand lines) I also have a complete list of products we can make on another sheet with the categories in column one.

I need to check if the 'pounds produced' each day is greater then the current 'best day' for the product category and if so, make it the new 'best day' value.

This will most likely be inserted into the macro I use to sort my data by manufacturing module. I have complete autonomy over this workbook so anything goes.