In 1922 Philadelphia retailer and US Postmaster General, John Wanamaker, said, "Half the money I spend on advertising is wasted; the trouble is I don't know which half."

Does this describe your restaurant advertising? How much of your advertising is being wasted?

It would be nice to know why each customer came to your restaurant, but that's not feasible or even possible.

For example, I went out for pizza last night. I went to a local pizza restaurant that I had not been to in over a year. Why did I go to that particular restaurant last night? "I don't know." I didn't see an ad and no one had recommended the restaurant. I just decided to go.

Likewise, even if you asked everyone why they came to your restaurant (regardless of what they say or write down), you won't always get the real answer because they may not even know.

The good news is that by asking, you will get enough real answers to know with a high degree of accuracy what advertising is working.

You don't have to ask every customer every day. You can get a very good idea of what's working and what's not working by collecting data for just one week. You can get this data from comment cards or by personally asking customers as they leave. Do it right and you will know more than most of your competitors.

I'm sure you have a handle on your food costs. Now do this one-week exercise and you'll know which half of your advertising expenses are being wasted. The results may greatly surprise you.