Steepness

 h – The proportion of unfished recruitment (R0) that would be expected to be produced if the spawning stock biomass was reduced to 20% of unfished levels. Steepness relates to fishery productivity and yield of the stock. For example, if steepness is 0.7, then reducing the spawners to 20% of unfished levels will reduce recruitment to 70% of unfished levels.This is a majors source of uncertainty for stock assessments.