ios - Text size issue in UITextView

Question

I have a UITextView and I need to calculate it's content size before the new character appears on editing. I've tried the following:

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
    CGSize size = [[textView.text stringByReplacingCharactersInRange:range 
                                                          withString:text]
                       sizeWithFont:textView.font
                  constrainedToSize:CGSizeMake(textView.contentSize.width, 200)
                      lineBreakMode:UILineBreakModeWordWrap];
    return YES;
}

I set a breakpoint at the line with return. The content insets are 0 each.

The problem is that the size has a height of 60, but the textView.contentSize.height is 76 (and I enter a character, not delete one so it should be 76 if no new line is required or greater than 76 if I`m at the end of line). Anyone knows why is this happening?

Thanks in advance!