Verified answer

If you discount the Protestants in the north (who were ship-builders and shop keepers) there was virtually no other industry in Ireland except farming. 99% (the one percent being catholic priests.)

Practically the entire population of Ireland worked as farmers, that is why when the potato famine hit so many people were devastated and led to the increase in immigration to America.

If you are asking about the irish population in America, then almost none of them were farmers; they took cheap jobs as factory workers.

60%