The series in Rosen's datasets are as follows:


   cows4.dat      data from Historical Statistics of the US and 
                  Agricultural Statistics;  the series are
	            1.  year
	            2.  U.S. population
	            3.  wholesale price index
	            4.  corn price per bushel
	            5.  hay price per ton
	            6.  value of land pe acre
	            7.  real gnp per capita
	            8.  consumption of beef and veal
	            9.  all cattle (including milk cows)
	            10. value of cattle per head
	            11. price of beef cattle
	            12. price of steers,per cwt
	            13. beef production, in million pounds
	            14. number of cattle slaughtered
	            15. number of milk cows
	            16. cattle - milkcows
	            17. cornprice/wpi
	            18. hayprice/wpi 
	            19. landprice/wpi
	            20. value of land /wpi
	            21. beefprice /wpi 
	            22. steerprice / wpi
   cxyser.dat     transformations of the data in cows4.dat (the
                  symbols match those in Rosen, Murphy, Scheinkman):
	            1.  y  (total stock, excluding milk cows)
	            2.  yrt (deviation of y from trend)
	            3.  ydif (first diff of y)
	            4.  x (breeding stock)
	            5.  xrt (deviation of x from trend)
	            6.  xdif (first diff of x)
	            7.  year
	            8.  c  (slaughter rate)
	            9.  crt (deviation of c from trend)
	            10. dc  (first diff of c)