The rate of a tax imposed under ECMC 3.05.010, as authorized by RCW 82.14.030(1), shall be one-half of one percent of the selling price or value of the article used, as the case may be; provided, however, that during such period as there is in effect a sales or use tax imposed by Grant County, the rate of tax imposed by this chapter shall be 425/1,000ths of one percent. (Ord. 240 § 2, 1985; Ord. 117 § 2, 1970)