For statistics relating to Northern Ireland, see the NISRA website:
http://www.nisra.gov.ukThere is no question that Catholics were prevented from working in certain industries, e.g. ship building, in the bad old days, and the old electoral system (based on property ownership) operated in favour of Protestants - which led to the (legitimate) protests in the 1960s, finally escalating into the violence of 1969.
There are still differences in evidence, but rather than dwelling on the gap between the communities it makes more sense to look at the enormous progress that has been made in reconciling their differences in recent years.
Furthermore, relations between the Irish Republic and Northern Ireland have also improved considerably. The border between the 26 counties and the 6 counties is no longer as obvious as it used to be and many of the unsightly army checkpoints and watchtowers have been removed. In fact, I have driven across the border many times without being aware of it.
Ulster, by the way, is not synonymous with Northern Ireland.
Northern Ireland consists of 6 counties of the province of Ulster: Antrim, Armagh, Down, Fermanagh, Londonderry (Derry), Tyrone.
The remaining 3 counties of the province of Ulster are in the Republic of Ireland: Cavan, Donegal, Monaghan.
Interesting Fact No. 1: St Patrick, the Patron Saint of Ireland, is closely associated with Roman Catholicism, but he is also the Patron Saint of the Church of Ireland, which is Protestant. St Patrick's grave - which he shares with St Colomb and St Bridget - is located in the cemetery of the Protestant Church of Ireland Cathedral, Downpatrick, County Down, Northern Ireland. I've been there - beautiful place!
Interesting Fact No. 2: There are separate national football teams for the Republic of Ireland and Northern Ireland but only one rugby team representing the whole of the island. With the Ireland rugby team representing both the Republic of Ireland and Northern Ireland, a new anthem, "Ireland's Call", was written to help cross sectarian and national divides and adopted as the rugby anthem in 1995. However, at home matches in Dublin the Irish national anthem, "The Soldier's Song" ("Amhrán na bhFiann"), is also sung.
As you have probably gathered, I love Ireland - North and South. I have visited the country at least 40 times.