I am using a macOS Sierra version 10.12.6. my wallet has been syncing since December 13, 2017 and is still at 60% and hardly advancing. Is this normal? Is there anything I can do to speed it up?
I've downloaded the blockchain many times (don't ask why). Maybe a week or so, just depends, I didn't keep track of the time frame at that point. If your network is slow, or your computer is slow (when verifying blocks), or if you're going through a VPN that slows you down, all those things could impact your download.
It is likely to be because your computer is slow validating the blockchain but not necessarily. This answer may help you.