Can system logs tell me when I closed my Macbook?
The last message before I opened my MacBook this morning was

5/19/19 22:43:36.000 kernel[0]: AirPort_Brcm43xx::powerChange: System Sleep 


I'm not sure I closed it at that time exactly last night but it was close.

I've just run an experiment now and it took about 15 seconds from my last activity before I close the lid until that message appears.