Varnish hit ratio 0

I have configured Varnish for a Virtual Host in my server with WordPress.

When I tried:

curl -I http://sportsmadeinusa.com/

My server response:

X-Varnish: 1471444842 1471444701
Age: 105
Via: 1.1 varnish

So I think Varnish is caching. But when I execute: varnishstat it returns zero in Hitrate ratio and Hitrate avg.

What is it happening? Is Varnish caching or not?

Thanks