Shrink DB Log

I never claim to be a DBA but I've had to take on some of the DBA type work since our DBA left. In SQL 2008 I have a DB with a very large transaction log that out backup system for some reason one clean up. Am i reading this right?

so the log allocated space 61536.69 MB then it says available space 60250.78 MB (97%) ... im thinking if i released the unused space it will clean up 97% of it so the log therefore it will shrink the log down quite a bit.