Difficulty of exercises

I'm interested in knowing the difficulty levels of the various exercises in gymnastics.

Someone had once told me that there are A to F levels of difficulty, with F being the most difficult.

Is there a list of difficulty evaluation? Like ring MU should be A.

What's the difficulty of the iron cross? Of the straddle planche?

etc.

Could someone please make a list with the most common exercises and their evaluations?

Code of points:

viewtopic.php?f=11&t=757

Off the topic of my head for the basic/static moves

NR - muscle up.... not rated. Basic skill. Used to be an A...

A - back lever, front lever, straddle planche (pbars/floor), handstand (rings, pbars, floor)

B - iron cross, rings straddle planche, full planche (pbars, floor)

C - inverted cross, manna, rings planche

D - maltese, butterfly cross

E - victorian

F - none except strength combos

G - none

Usually swinging moves or strength move into strength move (depending on) will increase the difficulty one letter grade. You can see which in the COP above.

Thanks braindx.

Strange that the handstand on the floor is A when the muscleup isn't.

Going from A to B is very hard, heh.