QQQ tracks the performance of the Nasdaq-100 Index, which represents the 100 largest non-financial companies listed on the Nasdaq Stock Market. QQQ is best known for providing investors with exposure to companies at the forefront of innovation across various sectors, including technology, healthcare and communication services. Over the past year, QQQ has gained 45% and led all inflows in late January. Late January marked a 1.4% gain in assets, and assets under management now stand at around $246 billion.