2018年一夜跌掉90%多的是做空VIX的ETPs - XIV and SVXY, etc...

当天VIX涨了100%，它们是做空一个月以后的VIX future, 虽然future白天没有涨100%。股市关盘后期货市场出现short squeeze, 典型的liquidity risk. 瑞银的XIV was liquidated. 只剩6%. 另一只SVXY改变法则，-1/2x track vix.  残喘延缓至今。On Monday, February 5, 2018, S&P 500 declined 4.1 percent and the value of the VIX more than doubled in a single day — for the first time ever. SVXY (Short VIX Short-Term Futures ETF) went from $428.76 (high) to $38.12 (low) - a drop of staggering 91.11%. At the time, funds' daily objective multiple was -1x the daily performance of the S&P 500 VIX Short-Term Futures Index. 为什么我记得这么清楚呢，因为损失惨重。用了两年才爬出来这么个大坑。