@Joseph C. Watts I am sharing excerpt from the documentation to find the size used by incremental snapshots.
Azure Disk Storage overview - Azure Virtual Machines | Microsoft Learn
You can see the used size of your snapshots by looking at the Azure usage report. For example, if the used data size of a snapshot is 10 GiB, the daily usage report will show 10 GiB/(31 days) = 0.3226 as the consumed quantity.
Please let us know if you have any further queries. I’m happy to assist you further.
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