If a cryptonote coin is using the original emissions structure, then the key variable here is EMISSION_CURVE_CHARACTER which (along with the block time) determines the rate of emission. Each integer increment represents a factor of two in emissions speed. In some of the code bases it is called EMISSION_SPEED_FACTOR.

So for example, Bytecoin uses 18 and Boolberry uses 20, making Boolberry 4x slower than Bytecoin. After adjusting for the block time, Monero is the equivalent of 19, putting it right in the middle of the two. Quazarcoin uses 21, so twice as slow as Boolberry. If I recall correctly Bitcoin (while using a different structure) is somewhere between 20 and 21.

Duck/dark/digitalnote uses a different structure altogether but is much, much faster than the others.