Those numbers are pretty low. Below spec in 4 and 6. Perhaps your rings are going? Don't you have only 41k miles or something? It's weird, because I checked my compression on my 41k Z a week ago and got very similar numbers, but found out later that I did the procedure wrong and didn't open the throttle bodies. Ended up with 140-145 across the board instead. But it says that you did open the throttle bodies, so I'm not sure.