I received a newsletter from a trade publication with this interesting case:
“The leading industry brand abruptly cut advertising, and traffic to its website quickly followed suit. While overall traffic dropped 75% in eight months, the drastic 90% decrease in direct traffic (buyers who type in a specific URL) reveals that consistent advertising frequency is vital in order to attract new buyers to a website.”

The chart shows the website going from 18,000 visitors/hits (chart shows both) a month to 4,500 over an eight month period. I’d be curious to hear how much their web-inquiries dropped during that same period.
In any case, an interesting tale of the power of trade-pub advertising. If you aren’t using print advertising, perhaps you should flip this chart and see how your site traffic could increase if you started advertising.
A B2B marketing blog by an honest-to-goodness marketing manager for an industrial manufacturer.