In V$Encrypted_tablespaces, why do so many of my encrypted tablespaces show 0 blocks encrypted?

Some tablespaces show large number of blocks encrypted, other tablespaces 0.  What's interesting is that even though it shows 0 blocks, it often shows millions of blocks decrypted.  The only info I could find on these columns, is that it's a running total.  I couldn't find anything saying there was an issue with the V$ENCRYPTED_TABLESPACES view.