For patient investors, fortunes have been made over the past year and change.

In the wake of the fastest decline of at least 30% in the S&P 500's history, investors have relished in a bounce-back rally for the ages. Between the March 23, 2020, bottom and May 11, 2021, the benchmark S&P 500 gained a cool 86%. Keep in mind that the historic annual average return of the S&P 500 is 7%, including dividend reinvestment. This puts into perspective just how impressive the returns have been over the past 13.5 months.

While it's not uncommon for the market's top performers to be small-caps stocks that are beginning to get noticed, a handful of large-cap stocks -- companies with at least a $10 billion market cap -- have significantly outperformed the benchmark S&P 500 over the trailing year. If you had the wherewithal, stomach, and luck to invest $200,000 into any of these four large-cap stocks, you'd be sitting on well over $1 million today.

A messy pile of one hundred dollar bills.

Image source: Getty Images.

Plug Power: $1.1 million

First up is hydrogen fuel-cell solutions provider Plug Power (PLUG 1.39%). Even after losing two-thirds of its value from its 52-week high, this alternative energy company is still up by close to 450% over the trailing 12 months. This means a $200,000 investment would now be worth about $1.1 million.

The buzz surrounding Plug Power primarily has to do with the growing push in the U.S. and globally toward clean energy solutions. President Joe Biden's victory in November, coupled with Democrats narrowly taking back the Senate in January, has made it plausible that a green energy bill could be passed on Capitol Hill. It's not yet clear what that would specifically mean for Plug Power, but any potential tax credits aimed at going green would be good news.

Plug Power also benefited from landing two major partnerships just a few days apart in January. SK Group took a 10% equity stake in Plug and plans to work with the company to develop hydrogen fuel-cell-powered cars and filling stations in South Korea. Meanwhile, French automaker Renault partnered with Plug to go after Europe's light commercial vehicle market.

Perhaps most important, the company provided a business update less than a week ago that calls for better than 60% year-over-year gross billing growth. Plug Power also reiterated its long-term guidance of $1.7 billion in gross billings by 2024, which would be more than triple the $475 million forecast for this year. 

A physician administering a vaccine into the right arm of a young woman.

Image source: Getty Images.

Novavax: $1.13 million

Among healthcare stocks, none has shown investors the green in a bigger way over the trailing year than Novavax (NVAX -8.32%). This predominantly clinical-stage biotech stock would have turned a $200,000 investment into a hearty $1.13 million.

As you may have guessed, the biggest catalyst for Novavax is the company's experimental coronavirus disease 2019 (COVID-19) vaccine, NVX-CoV2373. Rolls off the tongue, doesn't it? In a phase 3 study in the U.K., NVX-CoV2373 demonstrated 96.4% efficacy against the original strain of the virus and 86.3% against the common U.K. variant, which might I add has also cropped up in various parts of the United States. As a whole, Novavax's experimental vaccine led to 89.7% efficacy. That's an encouraging sign NVX-CoV2373 will be effective at tackling disease variants. 

However, Novavax has run into multiple delays with regard to filing for Emergency Use Authorization (EUA) in the United States, the U.K., and Europe. The company now anticipates filing for EUA in the third quarter, and it isn't expected to reach full production of the vaccine until the fourth quarter. There's clear concern that Novavax could miss out on the low-hanging fruit, so to speak, in the most lucrative developed markets. 

The good news is that Novavax is well capitalized, and the early indications seem to be that NVX-CoV2373 has a good chance of getting authorized on an emergency basis. The question is: How patient will investors be with the company?

A NIO ES8 electric vehicle in a showroom.

The NIO ES8 EV SUV. Image source: NIO.

NIO: $1.86 million

The second-best performing large-cap over the trailing year is electric vehicle (EV) manufacturer NIO (NIO 2.69%). Racking up gains of more than 830%, NIO would have turned a $200,000 initial investment into $1.86 million.

The bullishness surrounding NIO is similar to that of Plug Power. In essence, demand for clean energy vehicles is expected to soar in the years and decades to come. What makes NIO extra intriguing is that it's located in China, the world's largest auto market. By 2035, the Society of Automotive Engineers of China has forecast that half of all auto sales will be some form of alternative energy (95% of which will be EVs). This makes China a market ripe with opportunity.

NIO is also using an innovative strategy to boost its long-term margins and increase near-term demand. The introduction of a battery-as-a-service program last year offers its EV buyers battery replacement and upgrades for a monthly fee. In exchange for paying this fee, NIO is reducing the purchase price for its new premium EVs. It'll give up some margin and revenue now in favor of high-margin, predictable subscription revenue later. It's a smart way of keeping buyers loyal, too.

It's no secret that NIO, like most EV-focused auto stocks, has a lot to prove. It boasts a $57 billion market cap but has only produced 102,803 EVs since its inception. Profitability also looks to be a year or two away. It'll be worth watching to see how much the company can up its monthly output once semiconductor chip shortages are resolved. 

A man and woman seated on a couch while playing video games.

Image source: Getty Images.

GameStop: $6.17 million

But in order to hit the jackpot over the trailing year, you would have wanted to buy shares of video game and accessories retailer GameStop (GME 30.71%). With aggregate gains of nearly 3,000%, a $200,000 initial investment in GameStop would now be worth about $6.17 million.

The bulk of GameStop's huge gains over the past year boil down to an epic short squeeze that occurred in mid-January. Beginning that month, retail investors on Reddit began banding together to buy shares and out-of-the-money call options in stocks with high levels of short interest. At the time, GameStop was the only publicly traded company with a short interest, relative to float, of more than 100%. This made it the perfect target for a short squeeze.

Unfortunately, the dynamics that made GameStop such a perfect squeeze candidate in January no longer exist. Short interest has come down considerably, all while average daily trading volume has risen. This is to say that if short-sellers wanted to head for the exit, it wouldn't be difficult to do so. Without feeling trapped, there's little chance of a sustained short squeeze.

The bigger concern here is that GameStop's operating performance in no way supports its lofty one-year gains. Even though it's raised plenty of capital and eliminated its debt, the company's total sales plunged more than 21% last year. Having a brick-and-mortar operating model when gaming has gone digital puts GameStop between a rock and a hard place. Despite its ongoing transformation, it's going to be some time before it's back in the profit column.