Rising less than 1% through May, the price of gold kept pace with the S&P 500, which also rose about 1%. Surprisingly though, several of the market's largest gold stocks enjoyed double-digit gains last month, including Franco-Nevada (FNV 0.63%), IAMGOLD (IAG 5.59%), and Tahoe Resources (NYSE: TAHO). Let's dig in and see what drove their share prices higher.

Merrily down the stream

On the heels of a strong first-quarter earnings report, shares of Franco-Nevada climbed nearly 13% in May. A leader in gold royalties and streaming, Franco-Nevada reported a record 131,578 gold equivalent ounces sold in Q1 -- a 23.4% year-over-year increase. Consequently, the company also reported a record $172.7 million in revenue for the quarter. That strong performance was well reflected on the bottom line, where Franco-Nevada reported net income of $45.6 million, up 52% year over year.

Shiny gold bars lie next to each other.

Image source: Getty Images.

Turning from the income statement to the balance sheet and cash flow, we find even more justification for the bullish sentiment in May.Franco-Nevada ended the quarter with no debt and $283 million in cash and cash equivalents. Furthermore, the company reported a 20% year-over-year increase -- to $119 million -- in free cash flow.

The company's impressive financial performance was certainly not the only factor which led investors to drive the stock higher. During the earnings report, Franco-Nevada announced its 10th consecutive annual dividend increase. Investors will now receive a quarterly dividend of $0.23 per share -- a 4.5% increase over the previous amount of $0.22 per share.

Kicking the year off right

Like Franco-Nevada, IAMGOLD also benefited from a strong Q1 earnings report; the stock climbed more than 13% through the month. Operating four gold-producing mines on three continents, IAMGOLD reported a year-over-year increase of 12% in gold production, from 191,000 ounces to 214,000 ounces. That increase contributed to some solid top-line growth: The company reported $260.5 million in sales last quarter, up from $219.7 million in Q1 2016.

IAMGOLD also achieved success in controlling costs during the quarter, reporting all-in sustaining costs (AISC) of $992 per gold ounce -- a 8% improvement over the $1,084 AISC the company reported during the same period last year. And, inspiring confidence that it sees continued success on the horizon, management reaffirmed its AISC guidance range of $1,000 and $1,080 for the full fiscal year. If the company achieves the midpoint of this guidance, it will represent a 1.6% improvement over the AISC of $1,057 which it reported in fiscal 2016.

FNV Chart

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More and more gold records

Like its peers, Tahoe Resources reported strong Q1 results, which helped propel its shares upward by more than 14% in May. Its four gold-producing mines in the Americas delivered 119,100 ounces of gold in the quarter, generating record revenue of $251 million. The company's successful Q1 positions it well to hit its guidance target range of 375,000 to 425,000 ounces for fiscal 2017. 

A better-than-expected AISC of $860 per gold ounce helped Tahoe Resources translate more of its top-line success to the bottom line as well. Reporting record net income of $74.7 million, Tahoe Resources booked $0.24 in earnings per share -- the highest EPS it has reported since Q2 2014.

Beyond their excitement about the company's Q1 performance, investors also looked favorably on the company's outlook for the next three years. By 2019, management is targeting gold production of 500,000 ounces to 550,000 ounces -- an increase it expects to manage largely via a ramp up in production at the Shahuindo mine in Peru -- and AISC between $900 and $1,000 per gold ounce.

Investor takeaway

Franco-Nevada, IAMGOLD, and Tahoe Resources all gave shareholders plenty of reasons to celebrate with their Q1 earnings reports, but the companies also seemed to poised to continue their strong performances.

Investors should watch to see if Franco-Nevada can continue generating strong cash flow, which will help the company to implement further dividend increases. Likewise, investors should keep an eye on how well Tahoe Resources is achieving its gold production and AISC targets, which will allow it to safely continue its monthly dividend payments. Regarding IAMGOLD, investors should monitor the company's sound balance sheet, as it offers one of the more compelling arguments for investing in the company.