head sizes

I need a favor. Please.

I am crocheting baby hats but I'm not sure what most head sizes are.

Can you please tell me how old your baby is and what their head circumference is. It might also help me to have the measurement of just the crown of their head. Then I can get an idea of average sizes. I'm sure I could find a sizing chart but I thought this would be interesting to find out and I needed to post something else anyway.

Thanks in advance for your help. And hey, you might just be rewarded for your efforts. Just saying.