Well the platform is new, I believe it needs some time, but I am sure it will be good and that this is a project worth investing to.
- You probably mixed ICN and BLX
check those links:
https://coinmarketcap.com/assets/blockchain-index/
https://coinmarketcap.com/assets/iconomi/
ICN is supposed to be Iconomi's shares, while BLX is just a compilation of different currencies and the price rises or drops depending how the currencies in the index are growing
+BLX graph on CMC is rather new and might not be 100% accurate.