Stellar is a part of top20 altcoin index Coinoindex.comThe index includes top 20 alternative cryptocurrencies with largest capitalization and tracks the value of the portfolio (in BTC) in which each coin has a 5% share.
The index was created to be an analogue of Dow-Jones or S&P indexes for the altcoins arena.
Rules of index composition:
- Coin should be traded at at least three exchanges, with cumulative daily volume above $1,000 for last 14 days
- Coins that track a value of a certain asset (USD, CNY etc) cannot be included.
- Each coin in included in the portfolio with the same weight.
You can invest in the index by using NXT Asset Exchange,
NXT Asset ID 13634675574519917918 Asset tracks the index value, and constant buy/sell liquidity is maintained.
You can invest using NXT cryptocurrency (you can exchange BTC to NXT directly in the NXT client from
http://multigateway.org/ or at
http://coinomat.com) or BTC at
https://trade.secureae.com/ 
