Dear all,
I would like to examine the effect of initial leverage ratio on leverage ratio. I've got a panel table (id = gvkey, time variable = fyear) from compustat. For everey firm I generated a variable called initial leverage ratio which is the leverage ratio at fiscal year 1. My question is: How can I make a regression with the variable initial leverage as a regressor?

My table looks as follows:

gvkey fyear BookLeverage in_book_leverage
1000 1970 .3974589 .3974589
1000 1971 .4491988
1000 1972 .3516351
1000 1973 .3215286
1000 1974 .2925345
1000 1975 .2444258
1000 1976 .3610895
1000 1977 .4236002

1001 1983 .3454545 .3454545
1001 1984 .2937235
1001 1985 .5125712

1002 1970 .3232765 .3232765
1002 1971 .135775
1002 1972 .2200817

1003 1983 .1406965 .1406965
1003 1984 .1152773
1003 1985 .3359542
1003 1986 .2579871
1003 1987 .3433487
1003 1988 .4748157
1003 1989 .4476209

1004 1967 .2293033 .2293033
1004 1968 .3481061
1004 1969 .335549

Thank you in advance.