The only firms that can be surveyed for their employment data, both before and after the minimum wage was imposed or raised, are the firms that were there in both time periods—that is, the survivors. If there has been a net decrease in the number of firms, the employment in these surviving firms need not have gone down at all, regardless of a decline in employment in the industry as a whole. The firms surveyed are like the people who survived playing Russian roulette, which may well be a majority in both cases, though not an indicative majority in terms of the issue at hand.
