As per the CEO of ABSA's perspective, sensitivity analysis involves examining how changes in input values impact model outputs. With your modelling expertise, the CEO seeks insights into projecting the organization's annual revenue. In addressing this inquiry, undertake a sensitivity analysis highlighting the key variables influencing the organization's profitability. Enumerate and analyse these variables, and additionally, present a detailed Excel spreadsheet illustrating the sensitivity of the variables to demonstrate their impact on revenue projections over the course of $12$ months. Answer with references.