Updated Frames Per Second Counter

I made an update to my FPS counter. It is great to know the current FPS but the average FPS is also of great value. It gives you a better sense of how your game will perform over time. I also included a reset in case I need to test different areas of the game I'm working on. I thought I'd share the updates.

public class FramesPerSecond : DrawableGameComponent
{
    private float _fps;
    private float _updateInterval = 1.0f;
    private float _timeSinceLastUpdate = 0.0f;
    private float _frameCount = 0;
    private float _totalSeconds;
    private float _afps;
    private float _totalFrames;

    public FramesPerSecond(Game game)
        : this(game, false, false, game.TargetElapsedTime)
    {
    }

    public FramesPerSecond(Game game, 
        bool synchWithVerticalRetrace, 
        bool isFixedTimeStep, 
        TimeSpan targetElapsedTime)
        : base(game)
    {
        GraphicsDeviceManager graphics = 
            (GraphicsDeviceManager)Game.Services.GetService(
                typeof(IGraphicsDeviceManager));

        graphics.SynchronizeWithVerticalRetrace = 
            synchWithVerticalRetrace;
        Game.IsFixedTimeStep = isFixedTimeStep;
        Game.TargetElapsedTime = targetElapsedTime;
    }

    public sealed override void Initialize()
    {
        base.Initialize();
    }

    public sealed override void Update(GameTime gameTime)
    {
        KeyboardState ks = Keyboard.GetState();

        if (ks.IsKeyDown(Keys.F1))
        {
            _fps = 0;
            _afps = 0;
            _timeSinceLastUpdate = 0;
            _totalFrames = 0;
            _frameCount = 0;
            _totalSeconds = 0;
        }

        base.Update(gameTime);
    }

    public sealed override void Draw(GameTime gameTime)
    {
        float elapsed = (float)gameTime.ElapsedGameTime.TotalSeconds;
        _frameCount++;
        _timeSinceLastUpdate += elapsed;
        _totalFrames++;

        if (_timeSinceLastUpdate > _updateInterval)
        {
            _totalSeconds++;
            _fps = _frameCount / _timeSinceLastUpdate;
            _afps = _totalFrames / _totalSeconds;

            System.Diagnostics.Debug.WriteLine("FPS: " + _fps.ToString());
#if !ANDROID
            Game.Window.Title = "FPS: " + _fps.ToString();
#endif
            _frameCount = 0;
            _timeSinceLastUpdate -= _updateInterval;
            System.Diagnostics.Debug.WriteLine("AFPS: " + _afps.ToString());
#if !ANDROID
            Game.Window.Title += " - AFPS: " + _afps.ToString();
#endif
        }

        base.Draw(gameTime);
    }
}