The Northern Ireland economy grew by just 0.9% in 2018, an initial estimate has suggested.
It represents a significant slowdown on the 1.7% growth estimated for 2017.
The figures come from the Economic Statistic Centre of Excellence (ESCoE), a consortium of research institutions that work with the Office for National Statistics (ONS).
ESCoE uses official data to produce estimates of regional economic growth in the UK.
Its work suggests that London was easily the fastest growing region in 2018, with output expanding by 2.9%.
'Lagging substantially behind'
Estimated growth rates in all other regions were less than 2%, with the UK average at 1.4%.
The only region with weaker growth than Northern Ireland was Wales, where output increased by 0.8%.
Stuart McIntyre, a senior lecturer in the economics department at Glasgow's University of Strathclyde and an ESCoE researcher, said the figures suggest that London "continues to far outperform the rest of the UK".
"Scotland, the North West, South West and East Midlands saw growth in 2018 slightly faster than the UK as a whole," he added.
"Lagging substantially behind the UK as a whole were Wales, Northern Ireland and the East of England."