While this was 0.06 percent points higher than the 12.34% recorded in April 2020, there was an higher increase month-on-month.

The headline index increased by 1.17% (month-on-month) in May, 0.15% higher than the 1.02% recorded in April.

"The percentage change in the average composite CPI for the twelve months period ending May 2020 over the average of the CPI for the previous twelve months period was 11.79%, showing 0.08% point from 11.71% recorded in April 2020," the NBS said.

The CPI measures the average change over time in prices of goods and services consumed by people for day-to-day living. 

10,534 respondents spread across the country usually provide price data for regularly priced market items of 740 goods and services.

May's inflation point is the highest in two years since 12.48% was recorded in April 2018.

The NBS also disclosed that the urban inflation rate increased by 13.03% (year-on-year), from 13.01% in April 2020; while the rural inflation rate increased by 11.83%, from 11.73 % in April 2020.

On a month-on-month basis, the urban index rose by 1.18% in May 2020, from 1.06% recorded in April 2020; while the rural index also rose by 1.16% in May 2020, from the 0.90% recorded in April 2020.

The 15.04% (year-on-year) May 2020 rise in the food index was caused by increases in prices of bread and cereals, potatoes, yam and other tubers, oils and fats, fruits, fish and meat. 

The core inflation, which excludes the prices of volatile agricultural produce, stood at 10.12% (year-on-year) in May 2020, up by 0.14% compared to the 9.98% recorded in April 2020.

However, the core sub-index increased only by 0.88% in May 2020 (month-on-month), down by 0.05% compared with 0.93% recorded in April 2020.

The highest increases were recorded in prices of pharmaceutical products, medical services, repair of furniture, hospital services, passenger transport by road, motor car, bicycles, maintenance and repair of personal transport equipment, passenger transport by sea and inland waterways, paramedical services, motor cycles and hairdressing salons and personal grooming establishment.

The current upward trend in inflation started in September 2019 around the time President Muhammadu Buhari closed Nigeria's land borders allegedly because of the activity of smugglers.

The outbreak of the coronavirus disease (COVID-19) that has interrupted economic activities is also believed to have also played a part.