Center two labels in view with Visual Format Language

gistfile1.m

    self.stepLabel = [[UILabel alloc] init];
    self.stepLabel.text = @"0 Steps";
    self.stepLabel.textAlignment = NSTextAlignmentCenter;
    self.stepLabel.font = [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:50];
    
    self.historicalLabel = [[UILabel alloc] init];
    self.historicalLabel.text = @"Historical";
    self.historicalLabel.textAlignment = NSTextAlignmentCenter;
    self.historicalLabel.font = [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:50];

    [self.view setTranslatesAutoresizingMaskIntoConstraints:NO];
    [self.stepLabel setTranslatesAutoresizingMaskIntoConstraints:NO];
    [self.historicalLabel setTranslatesAutoresizingMaskIntoConstraints:NO];
    
    [self.view addSubview:self.stepLabel];
    [self.view addSubview:self.historicalLabel];
    
    NSDictionary *views = @{@"superview" : self.view,
                            @"stepLabel" : self.stepLabel,
                            @"historicalLabel" : self.historicalLabel};
    
    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[superview]-(<=1)-[stepLabel]" options:NSLayoutFormatAlignAllCenterY metrics:nil views:views]];

    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[superview]-(<=1)-[stepLabel]-(20)-[historicalLabel]" options:NSLayoutFormatAlignAllCenterX metrics:nil views:views]];