Hi all,

I have a quite extensive dataset. I included a small part (I have a lot more variables) of it below to demonstrate what I exactly want to do:

Code:
input double(issue_id issuer_id) str64 prospectus_issuer_name str6 issuer_cusip str4 issue_cusip str64 issue_name long maturity str4(security_level security_pledge) str2 enhancement str4 coupon_type str2(convertible mtn)
563203 39998 "HORIZON LINES INC"                 "44044K" "AD3" "GTD SR SECD MANDATORILY CONV SER B" 19271 "SS"   "" "Y" "F" "Y" "N"
564985 36988 "MCMORAN EXPL CO"                   "582411" "AL8" "SR NT CONV"                         19272 "SEN"  "" "N" "F" "Y" "N"
574487     3 "AAR CORP"                          "000361" "AK1" "SR NT CONV"                         19783 "SEN"  "" "N" "F" "Y" "N"
560467 34999 "GILEAD SCIENCES INC"               "375558" "AN3" "SR NT CONV"                         19844 "SEN"  "" "N" "F" "Y" "N"
539393 23164 "MASTEC INC"                        "576323" "AL3" "GTD SR NT CONV"                     19889 "SEN"  "" "N" "F" "Y" "N"
583599 43677 "EPALS CORP"                        "268791" "AA8" "SR SECD DEB CONV RULE 144A"         20027 "SS"   "" "N" "F" "Y" "N"
574893 37209 "JAKKS PAC INC"                     "47012E" "AD8" "SR NT CONV"                         20028 "SEN"  "" "N" "F" "Y" "N"
539435 23164 "MASTEC INC"                        "576323" "AM1" "GTD SR NT CONV"                     20072 "SEN"  "" "Y" "F" "Y" "N"
555375 41008 "SALESFORCE COM INC"                "79466L" "AB0" "SR NT CONV"                         20103 "SEN"  "" "N" "F" "Y" "N"
617801     3 "AAR CORP"                          "000361" "AR6" "SR NT CONV RULE 144A"               20120 "SEN"  "" "N" "F" "Y" "N"
568749 42255 "PDL BIOPHARMA INC"                 "69329Y" "AE4" "SR NT CONV SER 2011 RULE 144A"      20134 "SEN"  "" "N" "F" "Y" "N"
593773 37324 "PRICELINE COM INC"                 "741503" "AN6" "SR NT CONV"                         20162 "SEN"  "" "N" "F" "Y" "N"
560627 40982 "YRC WORLDWIDE INC"                 "984249" "AB8" "GTD SR SECD NT CONV SER A"          20178 "SS"   "" "Y" "F" "Y" "N"
569099 40982 "YRC WORLDWIDE INC"                 "984249" "AC6" "GTD SR SECD NT CONV SER B"          20178 "SS"   "" "Y" "F" "Y" "N"
568791 41191 "KAISER ALUM CORP"                  "483007" "AB6" "SR NT CONV"                         20179 "SEN"  "" "N" "F" "Y" "N"

My question is as follows:

I want to delete observations (rows) that have multiple matching criteria.
For example, if prospectus_issuer_name is the same(or 'duplicate') & maturity is the same & coupon is the same & issue_date is the same, only then I want all of the 'duplicates' removed and I want only 1 of them to remain.
So to be clear, only observations for all of the criteria are the same, then I want them deleted.
How would I go about this?

Thanks in advance!