After scouring the web for tools to provide me relatively accurate reporting on daily keyword reports I learned there was no quick fix. I say relatively because search engines don't like to release updated
information on search volume for particular phrases, and if they do it's very hard to come by.
Aaron Wall's www.seobook.com has one of the most comprehensive keyword tools that rival even some pay services. The site explains their results as a statistical divide across search engine popularity with Google in the lead, Yahoo at roughly half of Google's search volume and MSN about half of Yahoo.
As a matter of fact I'll let them explain how it works:
"The keyword tool effectively analyzes monthly search Data across Google, Yahoo and MSN. Please note our tool
currently assumes Google having double Yahoo!'s search traffic and Yahoo! having double MSN's search volume.
Depending on your topic / vertical and your geographic location the search engines may have vastly different search volumes. The tool can only possibly offer approximations. Exact search volumes are hard to find due to vanity searches, click bots, rank checkers, and other forms of automated traffic. Exceptionally valuable search terms show far greater volume than they actually have due to various competitive commercial forces causing greater automated search traffic."
So using these results and dividing them by how many days there are in a month (on average there are 30.416 days in a month if you're taking notes, and don't get me started on leap year) you will get a fairly accurate estimate of daily search volume for a particular key phrase.
This process will help you narrow down and help you make a more educated decision as to the keywords you will use for your PPC campaigns as well as determining your target audience. This in turn will lead you to creating more focused content, leading to more traffic and better rankings.