Mega-caps reclaim market leadership
SPY•Mega-cap technology shares helped the cap-weighted S&P 500 rise 0.23% in September, while the equal-weighted index fell 3.9%. The cap-weighted index is up 12.5% this year, versus 9.8% for its equal-weighted counterpart.
1. Mega-caps lead September gains
The S&P 500’s cap-weighted index is on pace for its biggest monthly gain relative to the equal-weighted index since May 2023, supported by September gains of 3.8% to 8.3% among the Magnificent Seven, semiconductors, communication services and large-cap technology. The ratio between the two indexes closed Thursday at 0.9039, near its May high of 0.9098.
2. Key levels to watch
The ratio rose from a late-July low of 0.8371 as mega-cap stocks regained ground. A move above the May peak would support a return to mega-cap leadership, while a drop below the 200-day moving average near 0.8674 could indicate the rebound is losing momentum. A fall below 0.8371 would undermine the longer-term uptrend described in the article.
