Answer the following question: Given the following passage  "Since the Carnation Revolution of 1974, which culminated in the end of one of Portugal's most notable phases of economic expansion (that started in the 1960s), a significant change has occurred in the nation's annual economic growth.[citation needed] After the turmoil of the 1974 revolution and the PREC period, Portugal tried to adapt to a changing modern global economy, a process that continues in 2013. Since the 1990s, Portugal's public consumption-based economic development model has been slowly changing to a system that is focused on exports, private investment and the development of the high-tech sector. Consequently, business services have overtaken more traditional industries such as textiles, clothing, footwear and cork (Portugal is the world's leading cork producer), wood products and beverages.",  answer the following question. Note that the answer is present within the text.  Question: What happened after 1974 that impacted Portugal's economy?
Answer:
PREC period