What is typical ROI with PPC advertising?

For the last few months I’ve been studying PPC advertising. There are many excellent books and blogs on the subject. However, almost nothing is specifically mentioned about gross ROI (gross return on investment)
Simply put, I’m trying to discover if many advertisers are receiving more than they spend for their adwords…. and by how much? What’s the ratio?
Here’s an example. About 19 years ago I ran a small newspaper ad campaign. It lasted for 3 months. For $30,000 spent in one newspaper, we received subscription revenue of $150,000. Those numbers are rounded off but bottom line, for every ad dollar spent, we received $5 back. That’s a 5:1 ratio of return to cost. Considering we used only small ads and all replies with cheques enclosed had to be mailed, the response was incredible.
But times have changed. Now we have the internet with easy payment options just a […]

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