Hi all,

I would like to find the largest % of institutional ownership for each deal, for example, finding the largest % of institutional ownership for deal_no 2041148040. I add some time conditions for finding the largest % of institutional ownership. In the first step, I want to get all observations that ann_date are larger than rdate. Then, I want to get all observations that only have the maximum rdate for each mgrno for each deal_no (i.e. one maxrdate for one mgrno for one deal_no). Finally, I want to get all observations that have the largest % of institutional ownership for each deal_no. I used -bysort- to realize it but it seems that I did not do it the right way. Codes and an example are as follows. Is there something that I did wrong? Could anyone help me to handle this problem?

Code:
keep if ann_date > rdate
bysort mgrno acusip6 ann_date (rdate) : gen seq=_n
bysort mgrno acusip6 ann_date(rdate) : gen seqmax = _N
gen maxrdate = rdate if seq == seqmax & rdate!= .
format maxrdate %d
drop if maxrdate==.
drop seq seqmax
gen pershrheld = (shrheld/(shrout*1000))*100 /*calculate % of institutional ownership*/
bysort deal_no (pershrheld) : gen seq=_n
bysort deal_no (pershrheld) : gen seqmax = _N
gen max_pershrheld = pershrheld if seq == seqmax & pershrheld!= .
drop if max_pershrheld==.
drop seq seqmax

Example:
Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input double mgrno str6 acusip6 int ann_date str10 deal_no double deal_value long rdate double(shrheld shrout)
110 "110122" 18100 "2093103020"  2247.397 17987   84544  1979863
110 "110122" 18100 "2093103020"  2247.397 18078   84544  1980883
110 "110122" 18100 "2093103020"  2247.397 18170   84544  1980925
110 "110122" 18100 "2093103020"  2247.397 18262   84544  1980980
110 "149123" 18231 "2133213040"    36.162 17987   22300   601527
110 "149123" 18231 "2133213040"    36.162 18078   22300   601752
110 "149123" 18231 "2133213040"    36.162 18170   22300   621294
110 "149123" 18231 "2133213040"    36.162 18262   19300   622728
110 "17275R" 17975 "2055874020"       590 17987   21200  5837017
110 "17275R" 17975 "2055874020"       590 18078   21200  5767881
110 "17275R" 17975 "2055874020"       590 18170   21200  5792675
110 "17275R" 17975 "2055874020"       590 18262   20200  5752585
110 "17275R" 18171 "2114183040"  3426.393 17987   21200  5837017
110 "17275R" 18171 "2114183040"  3426.393 18078   21200  5767881
110 "17275R" 18171 "2114183040"  3426.393 18170   21200  5792675
110 "17275R" 18171 "2114183040"  3426.393 18262   20200  5752585
110 "17275R" 18183 "2117364020"  2776.679 17987   21200  5837017
110 "17275R" 18183 "2117364020"  2776.679 18078   21200  5767881
110 "17275R" 18183 "2117364020"  2776.679 18170   21200  5792675
110 "17275R" 18183 "2117364020"  2776.679 18262   20200  5752585
110 "291011" 18176 "2115437020"  1108.804 17987    7130   755037
110 "291011" 18176 "2115437020"  1108.804 18078    7130   751441
110 "291011" 18176 "2115437020"  1108.804 18170    7130   751590
110 "291011" 18176 "2115437020"  1108.804 18262    7130   752278
110 "293792" 18016 "2069393020"  3283.249 17987   33240   449945
110 "293792" 18016 "2069393020"  3283.249 18078   33240   460249
110 "293792" 18016 "2069393020"  3283.249 18170   33240   476867
110 "293792" 18016 "2069393020"  3283.249 18262   33240   604716
110 "30231G" 18245 "2137370020" 40298.142 17987  152531  4941630
110 "30231G" 18245 "2137370020" 40298.142 18078  152531  4879710
110 "30231G" 18245 "2137370020" 40298.142 18170  152531  4805790
110 "30231G" 18245 "2137370020" 40298.142 18262  150881  4731898
110 "369604" 18234 "2133890020"      3800 17987  254830 10569000
110 "369604" 18234 "2133890020"      3800 18078  254830 10589575
110 "369604" 18234 "2133890020"      3800 18170  254830 10626842
110 "369604" 18234 "2133890020"      3800 18262  251830 10647495
110 "458140" 18052 "2079367020"   890.287 17987   33000  5562000
110 "458140" 18052 "2079367020"   890.287 18078   33000  5585000
110 "458140" 18052 "2079367020"   890.287 18170   33000  5598000
110 "458140" 18052 "2079367020"   890.287 18262   33000  5522000
110 "459200" 18106 "2094434020"   950.571 17987   65896  1814836
110 "459200" 18106 "2094434020"   950.571 18078   65896  1814836
110 "459200" 18106 "2094434020"   950.571 18170   64396  1814836
110 "459200" 18106 "2094434020"   950.571 18262   58892  1814836
110 "478160" 18038 "2075617020"   988.216 17987   21910  2767644
110 "478160" 18038 "2075617020"   988.216 18078   35860  2755566
110 "478160" 18038 "2075617020"   988.216 18170   35810  2755814
110 "478160" 18038 "2075617020"   988.216 18262   35810  2759100
110 "494368" 18179 "2116673020"   315.072 17987   19040   413997
110 "494368" 18179 "2116673020"   315.072 18078   19040   414206
110 "494368" 18179 "2116673020"   315.072 18170   19040   414493
110 "494368" 18179 "2116673020"   315.072 18262   16040   415379
110 "713448" 18007 "2066470020"  2060.375 17987   26700  1556731
110 "713448" 18007 "2066477020"  5421.629 17987   26700  1556731
110 "713448" 18007 "2066477020"  5421.629 18078   26700  1556791
110 "713448" 18007 "2066470020"  2060.375 18078   26700  1556791
110 "713448" 18007 "2066477020"  5421.629 18170   26700  1557999
110 "713448" 18007 "2066470020"  2060.375 18170   26700  1557999
110 "713448" 18007 "2066477020"  5421.629 18262   26700  1560445
110 "713448" 18007 "2066470020"  2060.375 18262   26700  1560445
110 "717081" 17923 "2044727020" 67285.695 17987  189475  6744640
110 "717081" 17923 "2044727020" 67285.695 18078  189475  6747979
110 "717081" 17923 "2044727020" 67285.695 18170  189475  6749143
110 "717081" 17923 "2044727020" 67285.695 18262  188415  8069536
115 "111320" 18231 "2132632020"       178 17897   20000   435900
115 "111320" 18231 "2132632020"       178 17897   20000   429800
115 "111320" 18231 "2132632020"       178 17897   20000   429650
127 "49446R" 18205 "2125038020"       444 17987 2199100   271084
127 "49446R" 18205 "2125038020"       444 18078 2880804   376352
127 "49446R" 18205 "2125038020"       444 18170 2794604   376366
127 "49446R" 18205 "2125038020"       444 18262 2975004   376751
135 "369604" 18234 "2133890020"      3800 17987   23700 10626842
135 "369604" 18234 "2133890020"      3800 17987   23700 10647495
135 "369604" 18234 "2133890020"      3800 17987   23700 10569000
135 "369604" 18234 "2133890020"      3800 17987   23700 10589575
155 "00724F" 18155 "2108492020"  1738.286 17987   34378   524207
155 "156708" 17910 "2042315020"       350 17987   12133    68809
155 "184496" 18016 "2069332040"   380.249 17987   86643    23749
155 "184496" 18016 "2069332040"   380.249 18078   89524    23328
155 "384802" 18052 "2079821040"       1.2 17987   13150    74480
155 "45666Q" 17940 "2050876020"        40 18078  259117    87137
155 "45666Q" 17940 "2050876020"        40 18170  297631    88365
155 "45666Q" 17940 "2050876020"        40 18262  318613    89450
155 "46612K" 18206 "2124946020"   414.883 18170  245673    31970
155 "46612K" 18206 "2124946020"   414.883 18262  268380    34515
155 "682189" 18205 "2128041020"        17 18078  762722   420353
155 "682189" 18205 "2128041020"        17 18170  876221   422099
155 "682189" 18245 "2137467020"   110.695 18078  762722   420353
155 "682189" 18245 "2137467020"   110.695 18170  876221   422099
155 "74762E" 18143 "2105124020"   337.217 17987   53119   196933
155 "74762E" 18143 "2105124020"   337.217 18078   17218   197631
155 "74762E" 18143 "2105124020"   337.217 18170   16716   197664
155 "74762E" 18143 "2105124020"   337.217 18262   16116   209171
155 "768573" 17917 "2044048020"        47 17987  279053    69147
155 "768573" 17917 "2044048020"        47 18078  194249    68501
155 "859241" 18234 "2135837020"      64.7 17987  251182    13190
155 "87929J" 18217 "2128380020"     1.935 18262  414559    42274
155 "87929J" 18232 "2133335020"       170 18262  414559    42274
155 "883556" 18143 "2076260040"   470.622 17987   25319   418165
155 "928563" 18119 "2098246020"       362 17987   38506    90654
end
format %d ann_date
format %td rdate
I would be very grateful for any help.

Best regards,
Wenyu