Section 1. Beginning January 1, 1998 and for a duration of four (4) years thereafter ending on December 31, 2001, monthly rentals of all residential units covered by Batas Pambansa Blg. 877 , shall not be increased by the lessor by more than the rates herein provided for:
PERIOD MAXIMUM INCREASE
January 1, 1998 - December 31, 1998 Fifteen percent (15%)
January 1, 1999 - December 31, 1999 Fifteen percent (15%)
January 1, 2000 - December 31, 2000 Fifteen percent (15%)
January 1, 2001 - December 31, 2001 Fifteen percent (15%)
Provided, That the basis for the maximum increase herein authorized for the four-year period shall be the actual monthly rental as of December 31, 1997: Provided, further, That the increase authorized herein shall be cumulative and compounded.