datetime - Subtract 1 hour from date in UNIX shell script

Question

I have the following in a shell script. How can I subtract one hour while retaining the formatting?

DATE=`date "+%m/%d/%Y -%H:%M:%S"`

Answer 1

The following command works on recent versions of GNU date:

date -d '1 hour ago' "+%m/%d/%Y -%H:%M:%S"