I have been wandering how many Mh/s of mining power is out there for scrypt.

As far as i can see the total network of litecoin is about 170.000Mh/s and dogecoin about 70.000. So combined its about 240.000Mh/s
Is there a way to find out how many Mh/s there is for all the other scrypt coins or to make an educated guess?