Stephen Gordon, "Stochastic Trends, Deterministic Trends and Business
Cycle Turning Points", Journal of Applied Econometrics, Vol. 12, No. 4,
1997, pp. 411-434.

The data used in the article are quarterly observations
for US Gross Domestic Product, measured in billions of
1987 dollars over the period 1947:1-1994:3 (191 observations).

The ASCII file `gordon.dat' contains three series: QRT, GDP and NBER:

  QRT indicates the date: 47.1 is the first quarter of 1947

  GDP is the raw data. The estimation results are based on the
  natural logs of these numbers

  NBER is the NBER reference business cycle, used in discussing
  the results. NBER=1 indicates an expansion, and NBER=0
  indicates a recession.

The data file looks like:


QRT     GDP  NBER

47.1  1239.5  1
47.2  1247.2  1
47.3  1255.0  1
47.4  1269.5  1
 :      :     :
 :      :     :
94.1  5261.1  1
94.2  5314.1  1
94.3  5359.2  1