The S&amp;P 500 aggregate index is now trading at 23x forward earnings. This means if you buy the index today, you’re paying $23 for every $1 of expected earnings, a valuation driven heavily by mega-cap tech.Meanwhile, the equal-weight index trades at just 17x.Here, every stock in the S&amp;P 500 counts the same, so it strips out the dominance of the largest companies.The gap shows how concentrated the market has become: mega-caps are inflating the aggregate multiple, while the “average stock” looks much closer to long-term historical levels.So the real question: is the premium on Big Tech sustainable, or does the market need to cool off?Source: StockMarket.News