MP = [(LEH - ERU)/(TLH - TEU)] X 100
where:
"MP" is the maximum percentage of the available housing tax credits allocated to developments in the subregion that may be allocated to developments reserved for elderly persons;
"LEH" is the number of low income elderly households in the subregion;
"ERU" is the number of existing units reserved for elderly persons in developments located in the subregion that already receive housing tax credits;
"TLH" is the total number of low income households in the subregion; and
"TEU" is the total number of existing units in developments located in the subregion that already receive housing tax credits.
Tex. Gov't. Code § 2306.6711