Large increase in broadband useage

[#1]

Hi, I'm on BBYW2 and last month went over my 15gb useage allowance.
I took a look at my previous months useage and it seems to be increasing quite drastically for no reason I can think of
Billing Period    Paid-for usage    Free usage        Total usage
06 Aug - 06 Sep  15.44GB              68.08MB                15.5GB
06 Jul - 06 Aug      12.14GB            70.96MB              12.21GB
06 Jun - 06 Jul      8.86GB              22.7MB                    8.88GB
It would have been slightly higher last month but I got a speed cut for the last day of the billing period.
When I look at the useage 'internet activities' it's mainly 'web browsing' - 80ish %
I can think of no great change in my web browsing activities from June until now, so is there an obvious reason for this increase? My connection is secure & I run Avast (free) anti-virus which is uptodate & was recently updated to v5.0.594 - all MS software is also uptodate
Any help or advice gratefully received.

[#2]

If you are using Windows install NetWorX on all your PCs and you can monitor your usage.
Do you have a wireless network enabled, if so is it properly secured?

[#3]

Thanks jelv I've just installed Networx.
My wireless connection is a secure one, but as I'm in a rural area I'd be able to spot anyone trying to nick my bandwidth!

[#4]

Quote from: rammie1976

but as I'm in a rural area I'd be able to spot anyone trying to nick my bandwidth!

Fair enough!

[#5]

We can provide an hourly breakdown of a day's usage so perhaps keep a log of your internet activities for a day and we can cross reference our logs and NetWorX.

[#6]

Thanks, first I'll see what sort of figures Networx throws up and compare them with Plusnet's 'VMU'. 

[#7]

HI rammie1976,
Just remember when doing your comparisons that the VMBU can take 2 hours to update.
Jojo