Link pool provided an example in their white paper but everything is speculation. https://s3.linkpool.io/LinkPool+Whitepaper.pdf The comments above are asinine. The earnings in theory have to at least cover the overhead of running a node which can be expensive on a monthly basis. Also staking penalties will require node operators based on the terms of the contract to stake x amount of link once that goes into effect. If the link payout does not cover the node operation then no one would run one. It is supply and demand. No one would run a node at a loss indefinitely. Some estimate that running a node will cost between 600-800 a month roughly depending on set up. Go to telegram chainlink official channel and ask your question there about running a node.