QUANDL was removed from tradingview.
We were using this data source to pull their BTC market cap and estimated transaction volume for BTC but unfortunately is no longer available.
For now I'll be using data from coin metrics since its the closest it can get to the actual NVT chart while I investigate better options, ask other NVT authors what are they currently using, etc.
We need a good source of "Estimated Transaction Volume in USD". We were using 'QUANDL:BCHAIN/ETRVU' symbol.