I want to know the answer to the following question:
In 1979, how much did the average per capita income change for Libyans?
All the background I'm provided with is that "It proved an economic success; while gross domestic product had been $3.8 billion in 1969, it had risen to $13.7 billion in 1974, and $24.5 billion in 1979.". Is that enough to answer the question?