Tourist consumption is the target index of this paper. This is because tourism consumption is the engine of the economic impacts of tourism not only in Okinawa but also in other destinations. In this paper, the method of decomposing the product of factors will be used to decompose tourist consumption in Okinawa. This is because consumption is the product of “number of visitors” and “per-tourist consumption.” Compared to the method of decomposing the sum of factors, the method of decomposing the product of factors is much more complicated. Therefore, there are few cases of applying this method. In this paper, the method will be applied to monitor the 5th Basic Plan for Tourism of Okinawa to ensure the effectiveness of that plan. According to the results of application of this method, it would seem to be difficult to achieve the goals of the plan even though only just past one-half of the planning period has passed.