Passenger traffic for Hawaiian Airlines in May was just below flat, the carrier reported Thursday; however, its efficiency markers were up and the carrier is investing in new technology to enhance operational performance.

Hawaiian carried 1,006,639 passengers — a four-tenths of a percentage drop compared with 1,o11,175 passengers in May 2018. However, Hawaiian’s load factor— or percentage of seats filled — increased by 1.4 percentage points to 87.3%.

Revenue passenger miles — or one paying passenger transported one mile — increased by nearly 6% to more than 1.5 billion. Available seat miles, or one seat transported one mile, rose more than 4% to nearly 1.8 billion.

For the year, passenger traffic has fallen almost 2% to nearly 4.8 million. The airline’s revenue passenger miles rose more than 3% to nearly 7.1 billion, and its available seat miles increased more than 3% to nearly 8.3 billion. Its load factor increased two-tenths of a percentage point to 85.5% from 85.3%.

Hawaiian, which made its traffic and expansion announcement after the market closed, saw its shares fall $0.13 to $26.23 during the regular trading session.

So far, 2019 has not been as robust as 2018 was for Hawaiian Airlines. Last year, the airline carried an all-time high of 11,840,178 passengers in 2018 amid a fleet expansion. Hawaiian’s passenger traffic last year rose 2.9 percent from 11,505,324 in 2017 as the airline took delivery of nine A321neo aircraft during 2018 to bring the size of its A321neo fleet to 11 aircraft.

But what the airline is missing in passengers, it’s trying to make up in efficiency and operational gains. Just after releasing its traffic statistics, the carrier reported today that it became the first U.S. airline to adopt the Pacelab Flight Profile Optimizer (FPO), software that uses satellite communication to continuously inform flight crews about winds, projected turbulence and aircraft performance.

Hawaiian said its Airbus A330 aircraft pilots “can access updated information on their tablets throughout the flight to make any needed adjustments to chart the quickest, most comfortable and fuel-efficient trajectory from take-off to landing.”

The enhancements, which are used on the 24 wide-body A330 aircraft that connect Hawaii to Australia, New Zealand, Japan, South Korea, Tahiti, American Samoa and the U.S. mainland, are expected to lower jet fuel burn beyond last year’s seven million gallon savings. Hawaiian expects the software will reduce annual fuel consumption by an additional 1% – approximately 1.3 million gallons. That would prevent more than 12,000 pounds of carbon emissions from entering the atmosphere.

Eventually, Hawaiian also plans to make the software available on its mid-haul Airbus A321neo narrow-body fleet. That fleet is expected to grow from 13 to 18 aircraft by early next year as the carrier, which is battling for West Coast positioning against Alaska Airlines and Southwest Airlines, increases service between U.S. West Coast cities and the Hawaiian Islands.