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  • Dustin Waybright thinks this is interesting:

index_type_desc  page_count  record_count  avg_page_space_used_in_percent
---------------  ----------  ------------  ------------------------------
HEAP             9           241           87.6465530022239

name           rows  reserved  data   index_size  unused
-------------  ----  --------  -----  ----------  ------
TestStructure  241   136 KB    72 KB  8 KB        56 KB

Note

From

Cover of Training Kit (Exam 70-461): Querying Microsoft® SQL Server® 2012

Note

You can see by the reserved amount being 8 pages larger than the data that SQL server has reserved an extent (9 pages of data - 1 IAM page) the size of the data to help manage fragmentation if data is added.