The national consumer price index (CPI) rose by 1.38 percent in December over the previous month, the highest monthly increase this year.

According to the General Statistics Office (GSO), the index has risen by 6.9 percent compared to the same period last year.

Experts say that the strong increase in the CPI two months before the Lunar New Year (Tet), which comes around in mid-February next year, is earlier than in previous years.

The main reason is probably because of the scarcity of certain goods, many of which are being stocked up for Tet and are pushing prices higher.

Of the ten commodities experiencing price increases, the cost of transportation has seen the highest rise of 2.47 percent due to rising oil prices. It is closely followed by food services at 2.06 percent, housing and construction materials 1.4 percent, drinks and cigarettes 0.97 percent and garments and footwear at 0.81 percent.

Meanwhile, postal services and telecoms are the only commodities to see a decrease of 0.11 percent.

On this basis, the GSO forecasts a yearly rise in CPI of 6.88 percent over last year, which meets the target set by the National Assembly.

Over the last 12 months, increases in the CPI have followed normal trends with strong rises in the first two months of the year due to the Tet holidays, and a sharp decrease the following month. Slight increases occur over the next seven months with larger increases following in the last two months of the year due to social investments and consumer spending. However the increases are under control, report financial commentators./.