No difference in size of my apk with cruncherEnabled option disbled

Question

I'm trying to reduce the size of my apk.

So first I've compressed my pngs with zopfli then added

aaptOptions {
    cruncherEnabled=false
}

in my build.gradle (app) and built.

But the result is same with and without that option (gradle version 2.2.3)

Can anyone help?