1 BTC = 8587.7823 USD (average from all sources)
1 BTC = 8574.99 USD (source: https://www.bitstamp.net)
1 BTC = 8711.94 USD (source: https://coinbase.com)
1 BTC = 8518.0 USD (source: https://kraken.com)
1 BTC = 8546.199 USD (source: https://poloniex.com)