The economic transformation also altered income structure. A noticeable shift was the reduction in wage differentials. The increased wealth produced by an advanced economy was distributed to wage earners via the system of broad income agreements that evolved in the postwar era. Organized sectors of the economy received wage hikes even greater than the economy's growth rate. As a result, blue-collar workers' income came, in time, to match more closely the pay of lower level white-collar employees, and the income of the upper middle class declined in relation to that of other groups.