What do the values for Get-MailboxStatistics for Exchange 2013 mean?

Hi,
I ran the following command on Exchange 2013 and got the output,


[PS] C:\Windows\system32>Get-MailboxStatistics -Identity mschmidt | select name, *size*


name                         :
TotalDeletedItemSize         : 143.4 MB (150,352,426 bytes)
TotalItemSize                : 3.212 GB (3,448,551,942 bytes)

MessageTableTotalSize        : 825.2 MB (865,239,040 bytes)
MessageTableAvailableSize    : 21.28 MB (22,315,008 bytes)
AttachmentTableTotalSize     : 2.202 GB (2,364,768,256 bytes)
AttachmentTableAvailableSize : 10.53 MB (11,042,816 bytes)
OtherTablesTotalSize         : 49.09 MB (51,478,528 bytes)
OtherTablesAvailableSize     : 2.094 MB (2,195,456 bytes)

I know what TotalDeleltedItemSize and TotalItemSize mean. Can anyone tell me what the other values (in bold) mean?

Also, in this case the total Mailbox size is = TotalItemSize or the addition of all the other values too?