Database
[{banks:[{name:"ABC",amt:0},{name:"PQR",amt:-1},{name:"XYZ",amt:3400}]},{banks:[{name:"ABC",amt:-2},{name:"PQR",amt:2344},{name:"XYZ",amt:7600}]}]
Query
db.collection.aggregate([{$project:{lessThanEqualToZero:{$reduce:{input:"$banks",initialValue:0,in:{$cond:[{$lte:["$$this.amt",0]},{$add:["$$value",1]},"$$value"]}}},greaterThanZero:{$reduce:{input:"$banks",initialValue:0,in:{$cond:[{$gt:["$$this.amt",0]},{$add:["$$value",1]},"$$value"]}}}}}])