If you’re invested in a broad market index fund and think you’re diversified, here’s a reality check. The information technology sector now accounts for 38.33% of the MSCI USA Index and a staggering 44% of the MSCI Emerging Markets Index as of mid-2026.
How we got here
Back in 2018, IT represented roughly 26.7% of the MSCI EM Index. By May 2026, that figure had ballooned to somewhere in the 35-40% range before pushing to 44%.
The primary catalyst is artificial intelligence. The insatiable demand for AI infrastructure, from training clusters to inference chips, has turned semiconductor companies into the load-bearing walls of global equity markets. NVIDIA, Taiwan Semiconductor Manufacturing Co. (TSMC), and Samsung Electronics have been the biggest beneficiaries, and their market capitalizations have dragged entire national weightings upward.
Taiwan’s weight in the MSCI EM Index rose by 0.30 percentage points to 23.76%, effective May 29, 2026, according to the latest quarterly index review. South Korea, along with Taiwan, accounts for approximately 44% of the entire MSCI EM Index through their tech and semiconductor holdings alone.
