Baggage Fees

On Tuesday, Harvard Business Review reported (via their iPhone app's stat of the day) that airlines experienced a 23.8% decline in lost bags last year. According to transportation IT firm SITA, airlines saved over $400 million because they lost fewer bags. Of course, the baggage fees drove these changes, as people checked far fewer bags. The airlines seemed to create a double win, collecting fees for checked luggage plus generating savings from fewer lost bags. However, I'd like to see one other statistic: how much additional revenue did Southwest generate through its "bags fly free" ad campaign? Did this swamp the cost savings and fee revenue other airlines generated?