How can you go from 7.7 gigs to 7.9 and then to 8.3 when you were without internet most of the time, due to a storm? When I did have internet it was too slow to load radar, much less stream anything.
Even if your Internet is slow (possible alignment problem), your modem uses data trying to connect, even if it's a poor connection. The system still uses small amounts of data to keep itself connected and talk back and forth from modem to system. I'll wager, the poor connection may require a little more data as the modem continues a persistent quest to connect itself and adjust the connection.....probably shooting bits back and forth doing self diagnostics and adjustments.
I have been experiencing high amounts of data loss this month too. Today, for instance, I haven't used the Internet at all, but somehow, I used 400MB in the last two hours. I checked my data this morning, and it said 6.6GB used. Two hours later, I received an email alert telling me I had used 70% of my monthly data. I checked again, and sure enough, it showed 7GB used! I have not been online at all, so how in the heck did 400Mb just vanish?