Higher hopes of the tax reform of being passed have acted as the latest catalyst in driving the Wall Street to new highs. In particular, the Nasdaq Composite Index gained 0.8% on the day, outperforming the other two benchmarks, the S&P 500 and Dow Jones, and hit the major milestone of 7,000 for the first time.

The surging technology sector, which accounts for nearly half of the index, as well as broad bullish sentiments helped Nasdaq to lead higher with a gain of 30% this year compared with gains of 25.5% for the Dow Jones and 20.2% for the S&P 500.

A combination of factors like improving global fundamentals, strong corporate earnings, a rising interest rate scenario, and the emergence of cutting-edge technology are acting as the key catalysts to these stocks. Consumer discretionary and industrial stocks on the index are also gaining on accelerating economic growth and rising consumer confidence. Rising oil prices, pick up in activities in most part of the world as well as improved global sentiments have added to the strength.

As a result, PowerShares QQQ QQQ, which serves as a proxy for the index, has climbed nearly 34% this year so far. Let’s take a closer look at the fundamentals of QQQ.

QQQ in Focus

This ETF provides exposure to the 107 largest domestic and international non-financial companies listed on the Nasdaq by tracking the Nasdaq-100 Index. It is one of the largest and the most popular ETF in the large-cap space with AUM of $59.4 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 delivered strong returns, a few were the real stars, having gained more than 80%. Below we have highlighted those five best-performing stocks in the ETF with their respective positions in the fund’s basket:

Top Performing Stocks of QQQ

Align Technology Inc. (ALGN – Free Report) : This stock makes up for just 0.25% allocation in the fund’s basket and has delivered incredible returns of nearly 145% this year. It has seen solid earnings estimate revision of 22 cents for this year over the past 90 days with an expected earnings growth rate of 50.32%. Align Technology has a Zacks Rank #1 (Strong Buy) and a VGM Style Score of D. Additionally, it belongs to a solid industry, having a Zacks Rank in the top 31%.