According to research from Chainanalysis, the use of Bitcoin ($BTC) as a payment method on dark web market sites doubled from the beginning of 2018 till years end, peaking at about $2 million per day. Overall, 2018 saw a lower volume spent than 2017, from $700 million to $600 million. Chainalysis correlates the 2018 increase in activity but drop in total volume to the closures of websites AlphaBay and Hansa in mid-2017, which caused a momentary market dip.