Dear statalists,
I’m using Stata 13.1 on Windows 7 and I’ve data from 2009-2012. I’ve calculated the market share of each company (i.e., comp_share). I would like to generate two variables, avrg1 and avrg2. Where avrge1 is the average market share of the largest four firms in the industry (i.e., sic) in a particular year (i.e., fyear) and avrg2 is the average market share of the next four firms in the same industry. I'm struggling how to write the code that can do the job.
I’ll be grateful for your help
My data is as follows;
I’m using Stata 13.1 on Windows 7 and I’ve data from 2009-2012. I’ve calculated the market share of each company (i.e., comp_share). I would like to generate two variables, avrg1 and avrg2. Where avrge1 is the average market share of the largest four firms in the industry (i.e., sic) in a particular year (i.e., fyear) and avrg2 is the average market share of the next four firms in the same industry. I'm struggling how to write the code that can do the job.
I’ll be grateful for your help
My data is as follows;
Code:
* Example generated by -dataex-. To install: ssc install dataex clear input long gvkey double fyear int sic double comp_share 7466 2009 1311 .34693896120538337 7039 2009 1311 .24536914522636577 1788 2009 1311 .19964407495505443 2437 2009 1311 .0563285125987912 8387 2009 1311 .03221220229948507 7137 2009 1311 .01837176803150096 1364 2009 1311 .012677270614497693 10743 2009 1311 .01092949211300734 10636 2009 1311 .009970299139304393 4358 2009 1311 .0078100297463560165 2845 2009 1531 .7568013650685039 7170 2009 1531 .06257041139580258 4546 2009 1531 .06125845115685833 6667 2009 1531 .0456344576729991 2772 2009 1531 .03559255797175098 6300 2009 1531 .02357305535713519 2937 2009 1531 .00417207650453138 10951 2009 1531 .004057557334738101 3406 2009 1531 .00321011547826784 8276 2009 1531 .002005516961004791 5737 2009 1531 .001124435098407754 8551 2010 2300 .2872246350348441 8551 2010 2300 .2872246350348441 6990 2010 2300 .2672462447145319 8219 2010 2300 .20127862301672336 7018 2010 2300 .11285172319086839 15471 2010 2300 .04255386574835588 5006 2010 2300 .03263484168495139 4014 2010 2300 .017462039700241145 6446 2010 2300 .013040506076967884 3043 2010 2300 .010500765091312968 7264 2010 2300 .010225362399760964 6348 2010 2300 .004981393341441993 9458 2010 2834 .46818866134587217 2950 2010 2834 .24732069816521957 7637 2010 2834 .08380594911560697 6315 2010 2834 .05364103198663614 4843 2010 2834 .04687661119016684 8026 2010 2834 .04219169983570156 4570 2010 2834 .039971264960437757 5364 2010 2834 .008538018932128936 8665 2010 2834 .006204156269119456 9227 2010 2834 .0018389050437556283 10902 2010 2834 .0014230031553548225 end