Polymorphic JSON Encoding ignores Subclass properties

output.json

{
  "name" : "Paul",
  "age" : 47
}

{
  "name" : "David",
  "age" : 28
}

PolymorphicJSONEncoding.swift

import Foundation

class Person: Encodable {
	var name: String
	var age: Int
	
	init(name: String, age: Int) {
		self.name = name
		self.age = age
	}
}

class Worker: Person {
	var job: String
	
	init(job: String, name: String, age: Int) {
		self.job = job
		super.init(name: name, age: age)
	}
}

var paul = Person(name: "Paul", age: 47)
var baker = Worker(job: "Baker", name: "David", age: 28)

var jsonEncoder = JSONEncoder()
jsonEncoder.outputFormatting = .prettyPrinted

var jsonDataPaul = try jsonEncoder.encode(paul)
var jsonPaul = String(data: jsonDataPaul, encoding: String.Encoding.utf8)!
print(jsonPaul)

print("\n")

var jsonDataBaker = try jsonEncoder.encode(baker)
var jsonBaker = String(data: jsonDataBaker, encoding: String.Encoding.utf8)!
print(jsonBaker)