What is the best way to interpret this chart of the value of the US dollar?

a href="http://fx.sauder.ubc.ca/cgi/fxplot?b=USD&c=XAU&rd=*&fd=1&fm=1&fy=1990&ld=31&lm=12&ly=2020&y=daily&q=volume&f=png&a=lin&m=0&x=" rel="nofollow"http://fx.sauder.ubc.ca/cgi/fxplot?b=USD…/a