How can I change text font in UIPickerView in iOS 7?

I was able to change my font color but I also need to change font size, how can I accomplish that? Here's my code for chaning the color,

 - (NSAttributedString *)pickerView:(UIPickerView *)pickerView attributedTitleForRow:(NSInteger)row forComponent:(NSInteger)component {
    NSString *title = _currencyName[row];
    NSAttributedString *attString = [[NSAttributedString alloc] initWithString:title attributes:@{NSForegroundColorAttributeName:[UIColor whiteColor]}];

    return attString;
 }

UPDATE: this didn't work:

 NSAttributedString *attString = [[NSAttributedString alloc] initWithString:title attributes:@{NSForegroundColorAttributeName:[UIColor whiteColor], NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-Light" size:40]}];