"GRE and Tobaccoville argue that, pursuant to § 600.22(10), a "units sold" occurs when a stamp is purchased by a licensed Oklahoma wholesaler. In effect, they argue that the number of units sold in a year is to be measured by the number of stamps purchased in a year because, as all the parties agree, the excise tax is collected when the stamps are purchased. GRE and Tobaccoville argue that, as a consequence, the NPM Reports that are prepared by licensed Oklahoma wholesalers, and that reflect the number of cigarettes in packs to which stamps - possibly purchased in previous years - have been affixed during that year, do not provide an adequate basis for calculating units sold...We reject this argument because the relevant language in § 600.22(10) states that units sold are to be "measured by excise taxes collected by the state on packs . . . bearing the excise tax stamp of the state." (Emphasis added.) That is, § 600.22(10) requires that the number of units sold be measured by the number of "packs, or 'roll-your-own' tobacco containers, bearing the excise tax stamp of the state," and not merely by the excise taxes collected. Not only does GRE and Tobaccoville's interpretation disregard this language, but to interpret § 600.22(10) in this manner would result in the unworkable attempt to measure the number of cigarettes sold in Oklahoma by individual NPMs based on the number of stamps purchased by wholesalers prior to those stamps being affixed to any particular brand of cigarette. We, therefore, agree with the State's assertion that "[i]t is true that the excise tax is collected when a stamp is purchased by a licensed wholesaler. However, after the tax stamps have been purchased, they still must be affixed to a pack of NPM cigarettes before a 'unit sold' upon which escrow is due occurs."11 We agree because when excise tax stamps are purchased from the OTC and the excise tax is thereby collected, the stamps could subsequently be placed on participating manufacturer cigarettes rather than on NPM cigarettes. Even if it were known that the stamps would be placed on NPM cigarettes, it would remain unknown how many packs of any particular NPM a wholesaler would take out of storage and stamp."