What are the characteristics of Ireland's economy? Why was Ireland's entry into the European Communities in 1973 a great boon to the nation's economy?

What are the characteristics of Ireland's economy? Why was Ireland's entry into the European Communities in 1973 a great boon to the nation's economy?

(1)For centuries the Irish economy depended heavily upon agriculture, but industry has contributed an increasing share to the gross national product since the 1960s.
(2) By 1978 Irish exports had gained duty-free access to the European Communities population market of 270 million people. Foreign companies, especially from the United States, established businesses or branch firms in Ireland to gain tax advantages in exporting to the European market. By 1990 about 850 foreign firms, 300 from the United States, owned operations in Ireland, resulting not only in new products and jobs, but also in additional skills, markets, and technology.