ASM: How much time the rebalance will continue?

When planning ASM changes/downtimes every DBA need to answer the query  "how much time the rebalance will continue ?". It turns out that to answer this question, you need to execute two commands only:

EXPLAIN WORK FOR + specify your ALTER DISKGROUP command, for example, alter diskgroup DATAC1 drop disk DISK1) 

And then query the V$ASM_ESTIMATE view:

EXPLAIN WORK FOR alter diskgroup DATAC1 drop disk DISK1;

SELECT est_work FROM V$ASM_ESTIMATE;
EST_WORK
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