GA does a pretty good job of filtering out most robots, plus you can use custom segments to filter out any that it hasn't spotted (some newer ones execute javascript etc). Plus we also use another piece of tracking software and both report similar numbers even though they track in different ways. Nothing will be 100% accurate but based on the traffic since 2006 there hasn't been any major spikes or drops, just a gradual climb in numbers.With regards to the 40k visitors, web server stats also count robots as they trawl the site as i found with my sites. I was getting 3000 visitors a month (classification of unique) but bts were counted in there so that throws the stats off and its not just 1 2 or 3 bots or even 10 20 30 its a lot. No 39900 though
