and the denominator of which is the sum of direct premiums written for insurance upon properties and risks everywhere plus premiums written for reinsurance accepted in respect to properties and risks everywhere. For purposes of this paragraph, premiums written for reinsurance accepted in respect to properties and risks in this state, whether or not otherwise determinable, shall be determined on the basis of the proportion which premiums written for reinsurance accepted from companies resident in or having a regional home office in the state bears to premiums written for reinsurance accepted from all sources.
Fla. Stat. § 220.151