The New Math of Grocery Shopping

by Matt Bell

It looked like the same type of advertising insert I'm used to seeing in our Sunday newspaper. It was from the grocery retailer where we do most of our shopping, with the usual store colors and formatted in the usual way. The sale price for laundry detergent caught my eye since it's one of those things we buy frequently. But when I looked more closely at the sale price, that's when I noticed the change. It listed a price, of course. But instead of also listing how many ounces the container held, it listed how many loads the detergent in this size container could wash. I'm used to comparing prices based on cost per ounce. Besides, the amount that I use per load is probably less than what the manufacturer recommends.

As I flipped through other advertising inserts, I saw that this appears to be a new trend. Several retailers mentioned only the number of loads that can be washed with the detergents they offered for sale. One listed both ounces and loads. Another still did things the old fashioned way, mentioning the price and the ounces. In one case, an ad listed a range of loads (72-96) that could be washed by the promoted detergent. However, the bottle stated a set number of loads (72).

A closer look during a visit to the detergent aisle showed that all of the detergents still list the ounces on the containers themselves, along with how many loads may be washed by the detergent in the containers. What made matters somewhat confusing, though, was the fact that different manufacturers' recommend different amounts of detergent per load, even within the same brand family. For example, a 200-ounce container of Cheer Original is promoted as being able to handle 64 loads, whereas a 200-ounce container of Cheer True Fit will handle just 52 loads.

And, just for fun, different manufacturers use different size containers. Whereas Tide and Cheer are offered in 100-ounce containers, Arm & Hammer offers a 120-ounce container (29 loads), Gain a 125-ounce container (30 loads), and Purex a 145-ounce container (35 loads).

A Procter & Gamble spokesperson said laundry detergent shoppers are accustomed to thinking in terms of loads, and highlighting loads rather than ounces helps people make sure they're using the proper amount for best results. However, the fact that different retailer ads now use different metrics — some still mentioning the ounces and some only mentioning the loads — makes it more difficult to compare prices.

What's a WalletWise shopper to do? If ever there was a need for a price book, now is the time. But we'll need to include more columns, at least for laundry detergent. We'll need to list the brands we prefer, the best overall price per ounce we've found, and also a calculation for price per load. For example, according to Procter & Gamble, a 300-ounce container of Tide Liquid can handle 78 loads, or "uses," as the company prefers. Since this size container was recently on sale for $16.49, my price book would contain a heading for laundry detergent, list the brand (Tide Liquid) on the far left side, indicate the price per ounce calculation of 5.5 cents ($16.49 divided by 300), and then include the price per load of 21 cents.

Adding loads to the laundry detergent section of our price book will help us cut through the confusion and save money. While it is in the best interests of the manufacturers to offer specialized forms of detergent that require more product per load, there's a significant difference between how many loads the basic forms of various detergents can handle. For example, while 300 ounces of Tide Liquid can handle 78 loads, according to the manufacturer, 300 ounces of Purex can handle 96 loads.

How far could this trend go? Will we see shampoo advertised by the number of hair washings? How will they normalize for those of us who, shall we say, don't need quite as much shampoo as we once did? Will we see toilet bowl cleaners promoted by their scrubbings per container? One sure bet: you won't see this trend in the snack food aisle. What manufacturer would dare limit consumption by putting the amount of potato chips or chocolates that a person should eat per snacking occasion on the front of their package?