The average number of vessels that passed through the Panama Canal in December increased to 34.2 per day, according to a notice from its authority seen on Jan. 13, but the waterway did not fill all the slots on offer, a sign that some ships continue taking alternative routes.

The canal, the world's second busiest and the only interoceanic way that operates with freshwater, between August and September lifted passage restrictions following a severe drought that forced a limit to daily transits and vessel drafts.

The Panama Canal Authority had been expecting a return to the full allotment of 36 transits per day, especially during peak periods, such as the last quarter of the year. But the open slots show many shippers have kept to their alternative routes.

In November, an average of 33.3 vessels transited through the waterway per day, while the average for October was 31.4 ships per day.

The canal's authority did not immediately reply to a request for comment.

Some vessels, including bulk carriers and LNG tankers, have continued using alternative routes when the cost of passing through Panama matches the extra fuel they must use to travel around the capes of Horn or Good Hope to transit between the Americas and Asia.

The canal's increase in passage fees in the last decade, something U.S. President-elect Donald Trump has recently complained about, has been an issue with some commodities producers and shippers, say analysts. Trump recently said he did not rule out using military or economic action to take over the canal.

In the fiscal year that ended in September, the canal reported a 5% decrease in its toll revenue to $3.18 billion, despite large declines in tonnage handled and the total number of vessels that passed through.

Between the 2020 and 2023 fiscal years, the canal's toll revenue had increased almost 26% to $3.35 billion, according to its annual reports.

The canal has said it expects in this fiscal year to achieve an annual tonnage close to the 511 million tons it handled in 2023, and see up to 12,582 deep-draft vessel transits between the Atlantic and Pacific Oceans.

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