What happened

Shares of Square, Inc. (NYSE:SQ) jumped by 154.4% in 2017, according to data provided by S&P Global Market Intelligence, after the company outpaced analysts' consensus earnings estimates throughout the year and expanded into new business segments.

So what

Square investors pushed the company's share price up early in the year after Square reported its fourth-quarter 2016 results at the end of February. Analysts were expecting the credit card payment-processing company to report a loss of $0.09 per share, but Square's loss came in at just $0.05 per share. That beat led to the company's share price jumping about 20% between February and the end of March.

Stock chart with numbers, green triangles and arrows on it.

Image source: Getty Images.

Square impressed its investors even further in May, when the company reported positive earnings of $0.05 in the first-quarter 2017, far exceeding Wall Street's estimates of a loss of $0.07 per share. That sent the company's stock spiking 26% in the month of May alone.

The company wasn't finished, though. In both the second and third quarters of the year, Square beat analysts' consensus earnings estimates. Earnings in the second quarter were 240% higher than analysts were expecting and 40% higher than Wall Street's estimates for the third quarter.

Investors were also optimistic about Square's growth beyond its mobile-payment business. News broke in September that the company filed paperwork to form its own bank so it can more easily loan money to small- and medium-sized businesses. Additionally, the company debuted a new point-of-sale register for large businesses in October, showing that Square is focusing more attention on larger -- and typically more lucrative -- payment customers. Shares of Square subsequently jumped 43% between September and the end of October.

The company's stock price retreated a bit in November and December, mostly after a downgrade from BTIG analyst Mark Palmer, but still ended 2017 up an impressive 154%.

Now what

Based on the company's third-quarter performance, Square's management raised its forecast for the full-year 2017. Sales for the year are now expected to be between $2.18 billion to $2.19 billion (formerly $2.14 billion to $2.16 billion), which represents a 45% increase at the midpoint, year over year.

Investors are already getting excited about the company's upcoming fourth-quarter 2017 and full-year 2017 report -- which will be released in late February -- and have pushed up Square's share price by about 15% since the beginning of January 2018.

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