Northern Ireland of course is much smaller than the southern Republic:
The difference between north and south — in 1926, for example — was crucial, agricultural and manufacturing sectors of the economy playing very different roles in the two jurisdictions. Almost 35 percent of the workforce in Northern Ireland were engaged in manufacturing, while under 10 percent were engaged in the nationalist Free state; nearly two-thirds of Ireland’s manufacturing employment was in the north.
That is from Richard English, Irish Freedom: The History of Nationalism in Ireland, pp.348-349. (By the way, this is one of the best books I’ve read in months. It is a subtle treatment of politics, history, religion, and most of all political psychology; it is especially strong on why the Unionist movement in the north never has perished and why a formal reunification of the two Irelands would be so hard to pull off.)
We also can learn that “In 1969 output per head in the [Northern] region was still around one-fifth higher than in the Republic.” And in 1984, living standards in Northern Ireland were about 25 higher than in the south.
Today “Northern Ireland’s per capita GDP is similar to that of the Border region of Ireland which is about 38 per cent lower than the national average.”
On Twitter, I suppose that would be #MNIGA.