If I am off of work for more than 4 days I am no longer as regular as I am at work. I think it has more to do with how much water a drink while at work (plus coffee), compared to my days off where I just sip water here and there. The worst thing is I have all day meetings every Monday and Tuesday until May with only 3 other people. Those days I can barely get away long enough to get in a nice 20 minute dump.