Figures from the Northern Ireland Composite Economic Index, published by the Northern Ireland Statistics & Research Agency, showed the private sector grew by 1.5% over the year.
The agency said the quarter’s fall in its public sector employment index might have been because it was “unduly impacted by the fact that the NI civil service underwent a period of strategic reorganisation in the form of a voluntary exit scheme which sought to reduce the number of such jobs”.
According to the index, economic output in all increased over the year, estimated at 1.2% in real terms.
A fall in the production sector was offset by increased activity in construction and services.
The agency said: “When the trend in the index is considered over the last three years there is some evidence that the rate of growth has increased.
“Annualised average growth over the last four quarters to Q3 2017 compared to the previous four quarters was 1.8%. This was higher than the annual growth over the previous two year period, which was 1.1%.”