The number of plastic bags bought across Northern Ireland has dropped by 70% since the 5p bag levy was introduced two years ago in April 2013.
This year 91.5 million single-use carrier bags were purchased across the province.
That compares to 300m in 2012, the year before the tax came in to play.
However, while the number is down on two years ago, this year's figures show that the number of single-use plastic bags purchased is up by seven million on the 84.5m sold last year.
In the second year of the programme, bag usage figures ranged from 21.8m in quarter one (April 2014-June 2014), to 24.8m in quarter three (October 2014-December 2014).
As in the first year of the scheme, the increase may be attributed to seasonal variations when there are more shoppers and tourists about.
Throughout every quarter of the second year of the scheme there was an increase in the number of bags notified as dispensed compared with the equivalent quarter of 2013/14 (year one).
There were increases of 12.1%, 4.3%, 3.2% and 14.9% in quarters one, two, three and four respectively.
The figures are based on data supplied by 3,150 retailers as notified by June 30, 2015.
However, the Department of the Environment suggests some of the increase may be explained by late figure submissions from the previous year.
The scope of the carrier bag levy was extended this year to include all carrier bags with a price of less than 20p.
Environment Minister Mark H Durkan said: "The response from shoppers again has been very positive and retailers continue to rise to the challenge.
"I commend them for that.
"I have always pledged that the levy on bags would be ploughed back into the environment and for the benefit of everyone.
"During the past year I have ensured money from the bag levy has gone back into the community through environmental projects," he added.
"I have been inspired by the great work being done.
"People pay the levy and I will continue to ensure that people get the benefit."