Here's what I learned from our developers and technical staff:
The green/red bar may be misleading. Each side doesn't have a separate meaning. It's just 1 magic percentage which indicates how "good" a product is for selling. Thumbs up and down just helps indicate which end of the bar is good and which is bad. The number just helps read the specific ratio. You will notice the two numbers always add up to 100%.
There are a few factors which may affect the 'magic percentage' like:
- eBay demand vs supply - lots of demand is a great thing!
- Pure number of listings on eBay.
- Number of times it's searched on Google (this is another demand-factor)
- number of results in Google.
- Does SaleHoo have a supplier for the product? - if you can't get it, you can't sell it!
Demand means at this single point in time, there's a certain number of posts on eBay requesting that one particular product.
The first set of results presented is a snapshot of the USA market. To get the numbers and statistics for other eBay sites (UK, Canada, Australia) you will need to do a full research on that particular product/keyword.
Hope this help :)