[{"campId":"61baef7817cd8ff66518",/**camp1*/"contactId":"61aa6fbf77490b0007714273",/** contact 1*/"title":"Happy Holidays!","communicationType":"EMAIL","contactedOnTime":{"$numberLong":"1695182032"/** AT TIME1*/},"communicationValidationError":"EMAIL_ADDRESS_NOT_PRESENT"},{"campId":"61baef7817cd8ff66518",/**camp1*/"contactId":"61aa6fbf77490b0007714273",/** contact1*/"title":"Happy Holidays!","communicationType":"EMAIL","contactedOnTime":{"$numberLong":"1695182074"/** AT TIME2*/},"communicationValidationError":"EMAIL_ADDRESS_NOT_PRESENT"},{"campId":"61baef7817cd8ff66518",/** camp1*/"contactId":"61aa6fbf77490b0007714274",/** contact2*/"title":"Happy Holidays!","communicationType":"EMAIL","contactedOnTime":{"$numberLong":"1695182059"},"communicationValidationError":"EMAIL_BOUNCED"},{"campId":"61baef7817cd8ff66518",/** camp1*/"contactId":"61aa6fbf77490b0007714274",/** contact2*/"title":"Happy Holidays!","communicationType":"EMAIL","contactedOnTime":{"$numberLong":"1695189792"},"communicationValidationError":"EMAIL_ADDRESS_NOT_PRESENT"}]

db.collection.aggregate([{$match:{campId:"61baef7817cd8ff66518"}},{$setWindowFields:{partitionBy:"$contactId",sortBy:{contactedOnTime:-1},output:{rankInLatest:{$rank:{}}}}},{$match:{rankInLatest:1}},{$group:{_id:{communicationValidationError:"$communicationValidationError"},totalErrors:{$sum:1}}}])