Indexing speed

My search/indexing started acting up in the last few weeks (constantly
indexing without ever finishing). So I'm trying to rebuild the index. The
index count is sloooooly going down. By my count, I have about 10,000 emails
throughout folders in my in-box, but Outlook seems to find about 25,000
"items" to index. It has been chugging away for about 3 full days, and is
finally down to about 12,000 items. This seems extremely slow to me, does
anyone have a good idea of how long it should take to index this many items?

I've adjusted the power settings to assure the machine is staying on
overnight to give it time to index while I'm not working, and to assure it's
not shutting down/rebooting to automatically install updates.

This is about 6 months worth of emails. I have many more in archive .PST
files. But because the indexing was going so slowly, I closed all my PSTs to
try to force Outlook to index the most recent emails first. But at this
rate, it's going to take like 3 weeks to index everything.