Six months ago I was laying <$30. Then I noticed a decline. I had a check on some Betfair results which showed it as marginal. I have since done a run on back data. which showed laying the fav only was no good, laying the top 2 or the top 3 was no good and laying those <$20 was no good. Or at least not worth the effort. Laying the field to a set liability was ok but erratic lost 2 months in a row. Currently trying to back some and lay the rest.