I now have a Thing in my calendar to prompt me to tabulate my spending each month too!
However, the bit where I compare it to a monthly average has just taken a bit hit (expected but depressing) in that last month was the month university fees were due, so, while per category stuff is on target, per month kinda explodes as nearly five grand in fees leaves my account. My brain is instinctively Unhappy about this, even though it's carefully budgeted for! Brains are not always terrribly sensible; solidarity for daft brains.