Lawson advertising is trying to persuade Kansas City Sailboard to spend more on advertising. The agency argument is that a constant strong and positive relationship exists between advertising and sales in the sailboard industry. Sue Lawson presents these data for stores similar in size and market share to Kansas sailboard

Advertising

expense annual sales

2500 96000

3000 110000

3500 124000

4000 138000

4500 143000

5000 147000

5500 150000

Using the high low method to estimate the relationship between increased advertising and sales

Amount of increased sales for every dollar of advertising