How many per episode?

Keep in mind that Kare Kano also used a lot of CG and drawings.

They skimped on cels.

Princess Mononoke had an absurd number of cels.
It had 150,000 I think, 80,000 which were key cels.

This is a record number of key cels used production, if I do recall correctly.

Well, think about it this way:
There are 24 minutes in an episode.
There are 60 seconds a minute.
There are 14 frames drawn per second.
There is at least 1 extra layer for every item that moves(eyes blinking/mouth opening/body moving)

Yeah, it's gonna add up to alot!

However, with computers, now the cel count can be absolutely zilch.

Shura, I think the "bank cel" is about to become your best friend...

I found this interesting article while trying to find out what an animation camera setup looks like. An interesting read, concerning how your cels get turned into anime. Written by permanent American anime convention fixture Scott Frazier:

http://sockfairy.com/scott/articles/BTS3.1-1.htm

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