With computers being so common place, and the number of POS systems out now, I see most of the businesses using them, NOT utilizing PMIX. And its typically the businesses that are struggling that fail to use it. PMIX is probably the lowest used feature on a POS system period.
PMIX is Product Mix. How many of each item sold. It even breaks each menu item all the way down to the glass of water. This is helpful in so many ways besides theft and portion control. You can also track the lowest selling items being offered. You want to remove those non-selling items from your menu that have no use.
Far too many paranoid owners/managers over populate their menus already, for fear that one person in 8 months may order that non-selling item they think they need to hold on to. They dont realize how much space its wasting when it could be replaced with something but more profitable and desirable. Utilizing walkin/freezer space is vital in this day and age.
By utilizing PMIX you can lower food costs by 20%. So learn PMIX! It will save you space, dead menu items and time/money in the end.