Total count of subscribed feeds fluctuating, as seen on right hand side of home page.

I see the total count of sites I am subscribed to, as seen on the right hand side of the home page fluctuate.

I could send a screenshot, 30 seconds apart, that show two different values.

In those 30 seconds no new feeds were added or deleted, but the count value changed from 191 to 181.

This has been happening for quite some time. Last 3 - 6 months at least, but just got down to reporting it now.