Payment processor WEX Inc. expects to see modest growth overall in 2016, despite flagging fuel prices and a bouncing world economy.

CEO Melissa Smith said the South Portland technology company, which got its start processing payments for companies with vehicle fleets, expects to see “significant growth” in its health care and international markets. The company, which released its year-end earnings report Monday reflecting a 5 percent increase in revenues, recently opened an office in Singapore, and within the last month has signed contracts with companies in China, Thailand and Indonesia.

“As (the international operations) scale up, they will ease the impact of fuel prices over time,” said Smith.

Fuel prices affect about 25 percent of the bottom line revenues in the company’s fleet division. WEX, which hedges against fuel prices, saw a significant drop in the value of its fuel price derivatives: in 2014 they accounted for $40.9 million in assets and only $5 million in 2015. The fleet division saw a year-over-year revenue decrease of 4 percent to $539 million.

The fleet division accounts for 65 percent of the company’s business. Its travel and health care segments make up the rest of the company’s portfolio.

Smith said diversification of the company will help offset the impact of fluctuating fuel prices, and represents enormous growth potential. Its travel division is now operating in 200 countries and saw a 13 percent increase in sales to $4.6 billion. And last year the company acquired Benaissance, a software billing company, for $80 million to expand its health care division.

In its earnings statement, WEX reported the travel division saw 7 percent year-over-year growth to $195.4 million and the health care division reported 66 percent growth to $120.2 million.

The company also announced its intention last year to acquire a competitor, Electronic Funds Source, for $1.5 billion, although that transaction hasn’t closed as yet.

“I think we have the right long-term strategy in place,” Smith said of the company’s diversification efforts.

For 2015, the company’s revenue increased 5 percent to $854.6 million from $817.6 million in 2014. Its net earnings, however, dropped from $202.2 million in 2014 to $101.9 million in 2015. Net earnings to shareholders were $2.62 per diluted share, compared with $5.18 in 2014.

For 2016, it expects revenue in the range of $860 million to $890 million and adjusted net income to fall between $148 million and $160 million. Shareholder earnings are expected to range between $3.80 to $4.10 per diluted share.

“Though we anticipate that the headwinds of 2015 will continue, we are confident in our ability to achieve organic growth in the coming year,” Smith said in a release announcing the earnings. “We believe the combination of this growth, coupled with our strategic investments, including recently announced acquisitions, position us well in the marketplace.”

Also reflected in its year-end statement is a $1.75 million penalty levied against it from the Federal Reserve for “deceptive” marketing practices used by Higher One, a partner of WEX Bank that disburses student loan money. WEX Bank issues the debit card used by Higher One.

In December, the Fed and the Federal Deposit Insurance Corp. ordered Higher One to make $30 million in restitution to 900,000 students for not telling them they had options beyond the company’s debit card to access their financial aid disbursements. As part of the finding, WEX Bank would have been liable for Higher One’s restitution payments if the student aid company couldn’t pay the whole amount.

Smith said Higher One has fulfilled its restitution order, and WEX paid its fine.

Founded as Wright Express in 1983, the company will continue to keep its headquarters in Maine, Smith said, where it employs about 700 people. But some employees will operate from new offices. WEX’s corporate headquarters remains on Gorham Road but some teams are moving from 97 Darling Ave. to nearby 123 Darling Ave. later this year.

Editor’s note: This is a corrected version of an earlier story that had the wrong address for WEX’s current location.