Crate Corporation, a calendar year taxpayer, has established nexus with numerous states. On December 3, Crate sold one of its two facilities in State X. The cost of this facility was $800,000.

On January 1, Crate owned property with a cost of $3 million, $1.5 million of which was located in X. On December 31, Crate owned property with a cost of $2.5 million, $700,000 of which was located in X.

X law allows the use of average annual or monthly cost amounts in determining the property factor. If Crate wants to minimize the property factor in X, which method should be used to determine the property factor there?