The Ministry of Finance said the country's fuel price stabilization fund had shrunk by 40 percent over the course of last year, to around VND 2.4 trillion ($110 million) in late December.
Compared to the end of September, that was up 9 percent.
The fund, established and managed by the ministry since 2009, extracts VND300 from every liter of fuel sold. Fuel companies are allowed to tap the fund when the government wants to keep prices stable and minimize the impacts of global increases.
The ministry's data showed that nine out of 27 trading firms had overdrawn last year. Most of these are small companies.
Meanwhile, state-owned fuel giant Petrolimex and Military Petroleum Corporation had $800 million and $12 million left at the end of last year.
Vietnam went through 25 fuel price adjustments in 2016, with more hikes than cuts. The latest increase was in late December when the popular gasoline grade RON92 hit VND17,594 per liter.
Fuel companies are currently given a subsidy of VND569 per liter from the price stabilization fund.
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