Linux how to check progress of DD

Few days ago I decided to install linux on Lenovo Yoga 1051f which is a Windows 10 tablet. First I wanted to create backup of existing system. This tablet has only 1 micro USB port so I had to use USB hub. I executed DD command for entire disk, that was about 32GB.

dd if=/dev/sdb of=/dev/sdc

After an hour or so I became curious about the progress. I expected this to be quick thing while it was very slow. Probably I should have done something like this:

dd if=/dev/sdb of=/dev/sdc status=progress

Copying was in progress and I didn't want to abort it. After doing some research I found a comment saying that I can open another terminal window and execute kill command there, then terminal where DD is running would show the progress. This indeed worked. In theory this should work too:

sudo kill -USR1 $(pgrep ^dd)

Happy dd-ing!