The correct usage is “companywide” as one word in the sentence: “I will employ the analytical skill set of economics to transform departmental data into tangible companywide information.”
Explanation: The term “companywide” is an adjective that describes something that applies to the entire company. In this context, it indicates that the information generated will be relevant to all departments within the organization. When used as a compound adjective, it is standard in English to combine words that convey a single concept into one word, hence “companywide” is the proper form. On the other hand, “company wide” written as two separate words is less common and generally not accepted in this context.