Google Analytics Glitch

Google Analytics shows that there is a change but how far it is true I am skepticle about. One fine day I was checking the stats of my sites on routine where I found that there was a drop in traffic in a week day completely down that I had never seen. That was a Shock for me as my site was never so in its History. Though I realized that there was no problem with my site by looking at the other 2 sites that were showing the same low stats in Analytics. Later on the next day I realized that it was fault in the update on Google's side.