CloudSQL instance has less storage usage after importing

I have a CloudSQL instance (PostgreSQL) with 112.7 GB data in it:

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I wanted to transfer the data in this instance to another one.

I did an export first and then created another instance and imported the data there.

All went good. However, the resulting instance has less storage usage, only 102 GB:

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No errors found in the logs. I am wondering where the 10GB data went.

Is this expected?