The preceding analysis also provides new evidence that TELs lead to increases in local sales taxes and income taxes. Few studies to date have examined the direct impact of TEL policy on these forms of revenues. Preston and Ichniowski (1991) find that TELs lead to increased nonproperty tax revenue, an aggregate category that includes local sales taxes, income taxes, other taxes, and miscellaneous general revenue, but do not separate the impact for each specific type of revenue. Although local sales taxes and income taxes have not been as widely used in municipalities as property taxes, these forms of revenues are playing more important roles in the face of shrinking property tax bases, especially in large cities. The impact of TELs on these revenue sources should not be overlooked.