some exceptions to this include the united states new zealand portugal and spain where the employment declines relative to output have been faster than historical norms see box for a discussion of the us case in the case of spain labour shedding has been so great relative to the fall in output that productivity which typically falls during a recession actually rose sharply while it was essentially constant in the united states although the link between a smaller employment response to recessionary shocks and a larger fall in labour productivity is purely algebraic it does provide a useful reminder that measures to preserve existing jobs in a recession are likely to imply significant costs and need to be subject to careful benefitcost assessments who bears the costs resulting from productivity declines during recessions is also important and depends in large part on how real wages adjust see discussion below why did okun s law break down in the united states during the recession