"Indexes" describe the market performance for a given set of cards similar to the S&P 500. We have indexes for all major categories, all players and even a few custom indexes such as the CL50. Each index has a graph that plots the value since the first sale that occurred in the index and uses our proprietary technology and vetted sales to describe the index. The index page also shows the growth over any time period.
These indexes serve an important purpose in the Card Ladder ecosystem. Our software uses these indexes to generate estimated values for all cards in the Ladder, sales in Sales History, and can be used to determine the value of cards in your Collection. We use points in time over the history of the Indexes for any given category or player and compare that relatively to another point in time. For example if the LeBron James index goes from 100 to 200 in a one year span we can logically predict a LeBron card in your collection will follow a similar path.