Self initialize error within Struct

I have a struct that gets data from my Firebase DB and populate a number of constants, this is to populate a TabelView on a seperate VC. initially I was trying to calculate distance from location in the tableViewCell class, but I want to be able to sort by distance, and read something about calculating the distance within the struct.

So I have moved my calculation to the struct asa func, and I am getting an error stating 'self' used before all stored properties are initialzed.

This is my struct and I have commented on the line where the error appears. What am I missing here?

import Foundation
import FirebaseDatabase
import CoreLocation

struct newTracks {

//Declerations
var locationManager = CLLocationManager()
let name: String!
let lat: Double!
let lon: Double!
let countryImage: String!
let link: String!
let ref: FIRDatabaseReference?
let distance: Double


//Initialize
init(name: String, trackId: Int, postcode: String, trackType: String, trackURL: String, locID: Int, lat: Double, lon: Double, phoneNumber: String, email: String, rating: Double, numrating: Double, totalrating: Double, countryImage: String, link: String, distance: Double) {
    self.name = name
    self.ref = nil
    self.lat = lat
    self.lon = lon
    self.countryImage = countryImage
    self.link = link
    self.distance = distance
 }

//Initialize data from Firebase
init(snapshot: FIRDataSnapshot) {
    let snapshotValue = snapshot.value as! [String: AnyObject]
    name = snapshotValue["name"] as! String
    lat = snapshotValue["lat"]as! Double
    lon = snapshotValue["long"]as! Double
    ref = snapshot.ref
    countryImage = snapshotValue["country"] as! String
    link = snapshotValue["link"] as! String
    distance = getDistance() //error on this line -- 'self' used before all stored properties are initialzed
 }

//calculate distance from current location to destination location
func getDistance() -> CLLocationDistance {
    let currentLat = self.locationManager.location!.coordinate.latitude
    let currentLon = self.locationManager.location!.coordinate.longitude
    let myLocation = CLLocation(latitude: currentLat, longitude: currentLon)
    let loc = CLLocation(latitude: self.lat, longitude: self.lon)
    let distanceInMiles = round(myLocation.distance(from: loc) / 1609.34)
    return distanceInMiles
}

func toAnyObject() -> Any {
    return [
        "name": name,
        "lat": lat,
        "lon": lon,
        "countryImage": countryImage,
        "link": link,
        "distance": distance
    ]

 }

}