Unable to get Kong Vitals to enable in enterprise version

I am evaluationg Kong API for recommendation and trying to fully explore the features.

I am using kong 2.3.2.0-alpine docker image with a postgres db. When setting the KONG_VITALS=on in the docker-compose file env vars, the resulting kong configuration still shows VITALS=false in the dev portal configuration list. Tried setting the value to on, true, 1 but no change. Are their other settings or conditions that must be met to use Vitals?

Thanks,
Jim Little