This appendix contains a listing of the municipalities in Puerto Rico and the tier applicable to each. Municipalities with average hourly earnings below $4.65 but equal to or greater than $4.00 are subject to Tier 2, as set forth below. Municipalities with average hourly earnings under $4.00 are subject to Tier 3. Municipalities which are listed under Tier 3 may pay the rates specified under Tier 4 to employees engaged in traditional activities, as defined in § 510.25 of the regulations. All other employees are subject to Tier 3. Municipalities which did not submit data are subject to Tier 1. The tiers set forth below are subject to petitions for review by affected employees, if filed prior to June 1, 1990. If upon review it is determined that the municipality should have been subject to Tier 1 or 2, back wages will have to be paid to April 1, 1990, to make up the difference between what municipal employees were paid and what they should have been paid.