Minecoins Value

in the "help section" for "Minecoins", there was no mention of how much Minecoins are worth in real money, like it's value to purchase. Maybe you could add something there for some common currencies for popular Countries that play the game for users to reference.

e.g. USD   $1 = 100 Minecoins

 Canadian $1 = 70   Minecoins

China        $1 = 650 Minecoins

OR

is it a flat rate all across the board (for all Countries) $1 = 100 Minecoins or something to that effect.  

That would be very helpful thank you