The tech-heavy Nasdaq Composite Index topped 15,000 for the first time ever driven by continued strength in tech stocks like Microsoft (MSFT - Free Report) , Nvidia (NVDA - Free Report) and Alphabet (GOOGL - Free Report) .

In particular, renewed optimism over the global economic recovery after the first full U.S. approval of a COVID-19 vaccine made by Pfizer (PFE - Free Report) and BioNTech bolstered risk-on trade. This is because the full approval will help squash the ongoing surge in the COVID-19 Delta variant and lead to a continued reopening of the economy. Additionally, strong corporate profit growth and ultra-easy monetary policies remain the major catalysts.

According to research firm Bespoke Investment Group, this is the sixth time the Nasdaq has crossed a 1,000-point threshold since the pandemic began (read: Buy These 7 Amazing ETFs Trading at Low P/E Ratios).

As a result, Invesco QQQ (QQQ - Free Report) , which serves as a proxy to the index, has also hit new highs, gaining 19.6% so far this year. Let’s take a closer look at the fundamentals of QQQ.

QQQ in Focus

This ETF provides exposure to the 102 largest domestic and international non-financial companies listed on the Nasdaq by tracking the Nasdaq 100 Index. Information technology accounts for 49.2% of the assets, while communication services and consumer discretionary make up for 19.5% and 16.1% share, respectively.

QQQ is one of the largest and most-popular ETFs in the large-cap space with AUM of $184.7 billion and average daily volume of around 32.7 million shares. It charges investors 20 bps in annual fees. The fund has a Zacks ETF Rank #2 (Buy) with a Medium risk outlook. Though most of the stocks in the fund’s portfolio have delivered strong returns so far this year, a few have gained more than 50%.

Below we have highlighted those five best-performing stocks in the ETF with their respective positions in the fund’s basket:

Top-Performing Stocks in QQQ

Moderna Inc. (MRNA - Free Report) : It is a clinical-stage pharmaceutical company, primarily focused on discovering and developing messenger RNA-based therapies. The stock has skyrocketed about 278% this year and has an expected earnings growth rate of more than 1000%. Moderna currently has a Zacks Rank #2 and VGM Score of B. You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.

NVIDIA Corporation (NVDA - Free Report) : This company is the worldwide leader in visual computing technologies and the inventor of the graphic processing unit, or GPU. The stock has gained about 67% and has an estimated earnings growth rate of 68% for fiscal year (ending Jan 22). It has a Zacks Rank #2 and Growth Score of B (read: Nvidia ETFs to Buy on Blockbuster Q2 Earnings).

ASML Holding N.V. (ASML - Free Report) : It is a world leader in the manufacture of advanced technology systems for the semiconductor industry. The stock has climbed nearly 65% so far this year and has an estimated earnings growth rate of 65.5% for this year. It has a Zacks Rank #2 and Growth Score of A.

Alphabet Inc. (GOOGL - Free Report) : It is one of the most innovative companies in the modern technological age. The stock has surged more than 61% and has an estimated earnings growth of 73.8% for this year. It has a Zacks Rank #3 and Growth Score of A (read: 5 Bargain ETFs to Tap Renewed Tech Strengthh).

Applied Materials Inc. (AMAT - Free Report) : It is one of the world’s largest suppliers of equipment for the fabrication of semiconductor, flat panel liquid crystal displays, and solar photovoltaic cells and modules. The stock has climbed nearly 52% so far this year and has an estimated earnings growth rate of 64% for the fiscal year (ending October 2021). It has a Zacks Rank #2 and VGM Score of B.

Zacks Names "Single Best Pick to Double"

From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all.

It’s a little-known chemical company that’s up 65% over last year, yet still dirt cheap. With unrelenting demand, soaring 2022 earnings estimates, and $1.5 billion for repurchasing shares, retail investors could jump in at any time.

This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.

Free: See Our Top Stock and 4 Runners Up >>