evidence: Workers paid at or below the prevailing federal minimum wage include only workers who are paid hourly rates. Salaried workers and other nonhourly paid workers are excluded. [...] Estimates of the annual average number of minimum wage workers for years when the minimum wage increased during the year reflect both minimum wage levels in effect during the year. For example, data for 2007 reflect the number of workers at or below the federal minimum of $5.15 for January to July and $5.85 for August to December. [...] Interpreting minimum wage data