This was due to stable food prices and a fall in oil prices, the statistics office said on Wednesday.
The figure is higher than average inflation in the region, a sign of fiscal problems facing the West African state, whose economy for years was seen as one of the continent's brightest due to its rapid growth based on gold, oil and cocoa exports.
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The government expects to secure a deal with the International Monetary Fund by the end of March for around 1 billion dollars in financial assistance aimed at stabilising inflation, reducing the deficit and restoring economic stability.
The government decreased oil prices by 10 per cent in January to reflect a global slump in fuel prices.
"The source of the easing is largely the stability in food prices that we have seen in recent months, supported by the decrease in oil prices," deputy government statistician Baah Wadieh told a news conference.
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January food inflation rose slightly to 6.9 per cent from 6.8 per cent the previous month, while non-food inflation stood at 23 per cent compared to 23.9 per cent in December, he said.
Mineral water, soft drinks and fruit recorded the highest inflation in the food group at 16.7 per cent. Housing, water, electricity, gas and other fuels saw inflation of 32.3 per cent, Wadieh said.