Young Brothers Ltd.’s interisland cargo volume rose slightly in the second quarter but stayed within the narrow range it has been stuck in for more than four years.

The state’s largest interisland cargo carrier said in a report due out today that volume edged up 1.2 percent from the year-earlier period with two ports on Hawaii island — Hilo and Kawaihae — contributing to most of the increase. It was the second positive quarter this year after a 0.2 percent gain in the January-March period.

Young Brothers’ annual cargo volume has been up marginally in recent years, with gains of 1.5 percent, 0.5 percent, 1.1 percent and 0.1 percent from 2013-16.

“This (second-quarter) positive outcome can be largely attributed to construction equipment and construction materials for the Big Island’s highway projects, as well as an increase in new and used automobile volumes,” Roy Catalani, vice president of Young Brothers, said in a statement.

While overall cargo was up, agricultural shipments dropped 5.3 percent primarily due to the closure of the Maui Farmers Co-Op, which previously used all three weekly Young Brothers sailings from Kahului to Honolulu to ship cabbage and Maui “Kula” sweet onions. Agricultural shipments from Kahului to Honolulu plunged 37 percent during the first half of the year largely due to the closure of Maui’s last sugar refinery, Hawaiian Commercial &Sugar Co.

The owner of Young Brothers, Seattle-based Saltchuk, said Thursday it will enter the mainland-‑ Hawaii cargo market soon with two new containerships being built in Philadelphia. TOTE, a subsidiary of Saltchuk, said it has signed a letter of intent to buy the two ships in 2020 and two more in 2021 from the shipyard in Philadelphia.

Young Brothers, which is regulated by the state, tracks cargo volumes using a standard unit measurement called container/ platform equivalents, or CPEs. For the second quarter the company’s interisland cargo volume of both inbound and outbound shipments totaled 33,583 CPEs compared with 33,200 CPEs in the year-earlier quarter.

Cargo volume jumped 8.4 percent in Hilo and 3.3 percent in Kawaihae on Hawaii island while increasing 9.7 percent on Molokai. Volume fell on Maui (4 percent), Lanai (2.5 percent) and Kauai (0.8 percent).

The agricultural sector continued to slump last quarter, led by a 39.8 percent drop in outbound shipments from Kahului. Honolulu shipments declined 10.4 percent.

However, agricultural shipments were up 16.7 percent from Kauai, 14.4 percent from Kawaihae, 2 percent from Hilo and 1.4 percent from Molokai.