From this post : Coinbase Index is a measure of the financial performance of all assets listed on GDAX, weighted by their market capitalization. Methodo

From this post : Coinbase Index is a measure of the financial performance of all assets listed on GDAX, weighted by their market capitalization. Methodology : https://am.coinbase.com/documents/cbi-methodology.pdf https://am.coinbase.com/documents/cbi-methodology.pdf The index level for CBI is calculated by dividing the sum of the current USD market capitalizations of all constituent assets by the Divisor I don't see how anything is weighted, it's just the sum of capitalizations expressed in USD divided by a weird divisor they control to keep the index smooth