![](/static/253f0d9b/assets/icons/icon-96x96.png)
Technically they don’t asymptotically go to zero. The minimum yield is the maximum of 20% or 20% of the original yield.
So at worst, an oil field will produce 2 oil/sec, which can still be bumped up by speed modules/beacons as well as mining productivity.
It’s not going to be enough alone for a large base, but I’d say it’s a lot better than almost useless.
Look out for cows in the air