4. Go to FRED Economic Data website. Obtain the data on daily yield-to-maturity on U.S. Treasury Securities for long-term and short-term (define long-term and short-term reasonably) from Jan, 1977 to Mar, 2022. In your response to this question, plot the difference between the yields of long-term and short-term securities.

(3 mark)

(a) Comment on its pattern in recent times. Discuss your rationale for your observations.

(2 marks)

(b) Discuss the time periods where you observe an inversion of yield curve. (3 marks)

Please limit your response within 300 words. No extra marks for a verbose answer.