How much do TV writers earn?

I'm not looking to enter the field, I'm just nosy. Would a writer on a sitcom like Modern Family earn more than a writer on The Late Show? Would a writer on the Late Show earn more than a writer on a cable show like Chelsea Lately or the Daily Show?

• I have heard that writers who write for sitcoms and dramas will usually make $30,000 per episode before agent and lawyer fees. I have also heard that make additional wages when they aren't the main or credited writers for other episodes. I'm not sure about variety or talk shows.

• I meant to say that the writers earn around $30,000 per episode for they are credited as the main writer.