Date format change

I am using graphite-web 1.1.0

I would like to change date format from m/d to d/m
I changed into grpahite server:
DATE_FORMAT = ‘%d/%m’

but it didn’t show that date format into X axis on my Icingaweb: i see the same m/d format.
What is my mistake?

thanks a lot

It was the solution.
Today I see that date format is %d/%m

it was only a matter of time