Freddy for those special nested JSON objects as data we have special names 
$key and $value
So when fetching this data - you would want to make a repeat region for example after it to display it.
Choose from your example: api2btcprice.data.bpi as a repeating expression.
Then inside the region you can populate the fields with $key to get the date and $value to get its value
Those are also available through the data binding pickup dialog
Soon we will be updating our charts component to handle also such data better directly and even make nice financial candlesticks charts that you need for stats