It’s become commonplace in news headlines to say millennials kill everything from romance to napkins, but now a survey shows they might be responsible for keeping the rally in bitcoin alive.A survey by venture capital firm Blockchain Capital found that about 30 per cent of those in the 18-to-34 age range would rather own $1,000 worth of Bitcoin than $1,000 of government bonds or stocks . The study of more than 2,000 people found that 42 per cent of millennials are at least somewhat familiar with bitcoin, compared with 15 per cent among those ages 65 and up.Bitcoin rose more than 6 per cent Wednesday to as much as $7,545, helping to push the value of the total cryptocurrency market above $200 billion for the first time, according to CoinMarketcap. The digital asset has soared more than 600 per cent this year, compared with gains of 15 per cent for the S&P 500 Index -- which might explain millennials’ attraction.While just 2 per cent of Americans own or have owned the cryptocurrency, according to the survey, that investor base might get larger as millennials become the main investment force. At that point, U.S. regulators may have approved bitcoin ETFs, and the derivatives market might be somewhat mature, making it easier for the new bitcoin buyers.