According to AT&T, i’ve averaged 70.85 GB per month over the past eight months. All my internet activities are through my PS4 & PS3. My high was 115 GB in the month after PS4 release. I have DSL, which AT&T desperately wants me to upgrade, so I’m capped at 150 GB.
Downloading games is the bandwidth hog. I was thinking about upgrading the PS4 HDD and going mostly/all digital but that might mean I’d be hitting the cap on occasion. Only other activities are online gaming and streaming video. Not watching a lot of Netflix though.