There are 13 X-Perp markets across three categories: seven US tech stocks (AAPL, AMZN, GOOGL, META, MSFT, NVDA, TSLA), two ETFs (SPY, QQQ), and four commodities (GOLD, SILVER, WTIOIL, BRENTOIL), all as USD expiry futures.How is the OKX X-Perp price calculated? OKX constructs a proprietary Index Price for each X-Perp using multiple weighted sources.