New research from Goldman Sachs reveals that U.S. Exchange-Traded Funds (ETFs) have surpassed the threshold of $8 trillion in assets under management (AUM), setting an all-time high this week.

This milestone is another clear indicator of the robust health of the investment landscape in the United States, as major stock market indices trade at or near their record levels.

The S&P 500, for instance, has rallied by 25% year to date, trading at a mere 1% distance from its all-time highs. Tech stocks in the Nasdaq 100 have soared 53% year to date, hitting a record high on Tuesday.

But the increase in the ETF market size isn't just about a bullish stock market. Rising assets among U.S. ETFs have also been driven by the influx of fresh capital from investors, as a testament of a broader optimistic sentiment.

Statistics from ETFdb.com shows that the SPDR S&P 500 ETF Trust (SPY  ), the largest ETF globally, saw an impressive $30.8 billion of inflows in December, raising its AUM to $478 billion. Similarly, another ETF tracking the S&P 500, the Vanguard S&P 500 ETF (VOO  ), witnessed $5.5 billion of inflows this month. The Invesco S&P 500 Equal Weight ETF (RSP  ) also saw inflows, amounting to $4 billion.

Investors have shown a keen interest in bond-related ETFs as well. For instance, the iShares 20 Year Treasury Bond ETF (TLT  ) has witnessed $3.6 billion of inflows so far this month, underlining the diversity of investor interest in both equity and bond markets, as the Federal Reserve's stance shifts.

Here are the top 10 U.S. ETFs with over $100 billion in assets:

ETF NameAsset ClassTotal Assets ($MM)YTD Price ChangeAvg. Daily Share Volume (3mo)Previous Closing Price

  • SPDR S&P 500 ETF TrustEquity$459,32025.29%83,028,508$471.97
  • iShares Core S&P 500 ETF (IVV  ) Equity$396,81825.41%5,025,149$476.15
  • Vanguard S&P 500 ETFEquity$370,01925.44%4,786,040$435.54
  • Vanguard Total Stock Market ETF (VTT  ) Equity$344,29125.04%3,440,999$236.33
  • Invesco QQQ Trust Series I (QQQ  ) Equity$226,72053.54%50,701,398$407.08
  • Vanguard FTSE Developed Markets ETF (VEA  ) Equity$120,81214.85%11,897,938$46.65
  • Vanguard Value ETF (VTV  ) Equity$106,3218.14%2,694,169$148.94
  • Vanguard Growth ETF (VTG  ) Equity$105,54046.26%924,069$310.27
  • iShares Core MSCI EAFE ETF (IEFA  ) Equity$104,98515.03%8,991,273$69.57
  • Vanguard Total Bond Market ETF (BND  ) Bond$103,5444.92%7,811,976$73.25