In a note to investors on Monday, RBC Capital Markets analyst Amit Daryanani said that Apple could surpass a $1 trillion valuation within the next 12 to 18 months. The analyst, who isn’t the first to float the idea, said that a host of “levers” could ultimately help Apple reach the $1 trillion mark, including revenue growth, improved margins, and higher earnings.

“We believe the fundamental reality remains that Apple’s valuation is materially sub-par to what we anticipate is its long-term revenue and earnings-per-share potential,” Daryanani wrote to investors.

Apple (AAPL) is currently valued at a little over $800 billion, which means the company would need to boost its shares rather quickly to reach $1 trillion. However, Apple’s valuation has been soaring in recent months, thanks to a growing share price. This year alone, Apple’s shares are up 32% to $153.33.

Apple hit the $800 billion market earlier this month after Drexel Hamilton analyst Brian White raised his price target range to $185 to $202. If Apple hits that range, the company’s market cap would reach $1 trillion. Like Daryanani, White believes Apple’s shares are undervalued at their current level and thinks the company’s financial performance will only improve in the next year. His range prediction suggests Apple could reach the $1 trillion mark within the next year.

No company has ever exceeded a $1 trillion valuation, which makes the possible feat all the more important. However, while Apple is considered the frontrunner in a race to $1 trillion, several other companies might get there first.

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In March, for instance, Barclays analyst Ross Sandler said Amazon might get there first, thanks to a soaring stock price and market cap. At the time, Amazon (AMZN) had a $424 billion market cap, but Sandler said its value growth is accelerating. As of this writing, Amazon is valued at $463.6 billion.

Several other companies—including Microsoft (MSFT) and Alphabet (GOOGL)—have also been floated as possible $1 trillion companies, though their market caps—$525.3 billion and $658 billion, respectively—are still far behind Apple’s.

While Daryanani didn’t say whether Apple would be first to reach $1 trillion, he did say that the company’s success is built not only on hardware, like smartphones and Macs. He told investors that Apple’s mobile operating system iOS creates an opportunity for Apple to keep generating revenue long after customers buy hardware.

“Simplistically, the scale of users attracts application developers, which in turn bolsters the number of users,” Daryanani said of iOS. “We believe this cycle results in a captive consumer base that transitions more data and usage via iOS on Apple devices.”