How to further filter query results in mongodb group’s finalize method

  mongodb, question

db.TruckUsers.group({
key:{PhoneNumber:true},
initial:{Count:0},
reduce:function(doc,prev)
{
if (! prev.PhoneNumber)
{
prev.PhoneNumber = doc.PhoneNumber;
prev.Count = 1;
}
else if(doc.PhoneNumber == prev.PhoneNumber)
{
prev.Count++;
}
},
finalize:function(doc)
{
for(i in doc.Count)
{
if (doc.Count > 1)
{
doc.NewPhoneNumber = doc.PhoneNumber;
doc.NewCount = doc.Count;
}
}

delete doc.PhoneNumber;
 delete doc.Count;
 }

})

I want to display only the records with Count>1, but I don’t know how to start. now this result will display all the records, as follows:

"28" : {},
 "29" : {},
 "30" : {},
 "31" : {},
 "32" : {},
 "33" : {},
 "34" : {},
 "35" : {},
 "36" : {},
 "37" : {},
 "38" : {},
 "39" : {},
 "40" : {},
 "41" : {
 "NewPhoneNumber" : "18217039***",
 "NewCount" : 3
 },

You can use the match property of aggregate to implement