Reduce vhdx size?

[Dog80]

I have a vhdx file that is 20GB in size. However, the data inside is just 5 GB. Is it possible to reduce the size so it fits in a 8GB flash drive?

[yoyodyne]

http://blogs.msdn.com/b/virtual_pc_guy/archive/2012/05/07/shrinking-a-virtual-hard-disk-in-windows-8.aspx or Resize-VHD (Hyper-V) | Microsoft Learn