Campbell, John Y.; Viceira, Luis M.; Sunderam, Adi - National Bureau of Economic Research (NBER) - 2009
The covariance between US Treasury bond returns and stock returns has moved considerably over time. While it was slightly positive on average in the period 1953--2009, it was unusually high in the early 1980''s and negative in the 2000''s, particularly in the downturns of 2000--02 and 2007--09....