I have time series for 3 stock portfolios ("0","5" and "10") with data for R&D spending ("pfxrd") and portfolio return ("pfrt"). For each Portfolio ("pf") I want to calculate the average portfolio return over ten years following the initial year of R&D spending. I will provide the data and elaborate a bit more on it then:
- Code: Alles auswählen
* Example generated by -dataex-. To install: ssc install dataex
clear
input float(year pf pfxrd pfrt)
1962 0 0 2.0433624
1963 0 0 3.235416
1964 0 0 2.0289717
1965 0 0 4.715116
1966 0 .77 2.840973
1967 0 .48 .876097
1968 0 1.41 2.4592624
1969 0 7.08 -.6605892
1970 0 0 .4436268
1971 0 0 2.881102
1972 0 0 1.0571196
1973 0 0 -3.090473
1974 0 0 -2.3816926
1975 0 0 5.344191
1976 0 0 2.180875
1977 0 4.44 .6919739
1978 0 6.248 1.340753
1979 0 8.422 2.3498313
1980 0 12.246 3.059075
1981 0 13.362 .8223675
1982 0 19.994 4.2377257
1983 0 34.747 2.1897767
1984 0 49.399 -.07765996
1985 0 54.386 2.788236
1986 0 109.911 1.9860017
1987 0 296.832 1.192912
1988 0 7507.789 2.677546
1989 0 7573.345 1.8918866
1990 0 8001.991 .7434589
end
format %ty year
Example: In 1966 the R&D spending of portfolio 0 was .77. I would like to get the portfolio return for 1 year after that date, 2 years after that date,....and 10 years after that date. This should be done for each portfolio and each year where R&D spending is positive. After that I would like to calculate the mean values of those returns for 1-10 years after R&D spending. Can anybody provide some advice, please?
Any help is much appreciated.
Best,
Alex