I think graphs and charts are great to explain and demonstrate things in a colorful, easy to understand fashion.
One way I use graphs in my business is to show my sellers how I track their home's online activity and keep a running total of how many people have viewed it.
Visual Tour.com offers a great graph with page views of each virtual tour.
The Visual Tour folks give you several options to automatically syndiate your listings.
KnoxvilleHomeCenter.com is my personal website and each of my listings is a "Featured Home" there.
kaarmls.com is my Association public idx website.
Realtor.com is NAR's official website
FrontDoor.com is HGTV's online real estate site
"Other" can include: Google Base, Homes.com, The Real Estate Book, Yahoo Real Estate, Zillow.com, HomeSeekers.com, Trulia, HomePages.com, Prudential Properties VOW, and Vast.com.
Below is the weekly viewer breakdown for one of my listings on Realtor.com.
This chart demonstrates that over 1600 people have viewed this listing on Realtor.com during the past 3 months or so.
Below is the number of real estate transfers recorded in the Knox County TN Register of Deeds office during a 1 week period broken down by price ranges.
This is our days on market summary for the past 9 years.
You'll notice our average days on market hasn't changed significantly over the past 9 years. I found that fact interesting. Virtually same time to sell in both good market and not so good.
I also get data from other sources. A statistical service called The market edge furnishes this information on residential building permits in Knox County Tennessee
Graphs and charts do great job of telling a story to buyers and sellers in a way that instantly easy to understand rather than just throwing raw numbers at them.