Background: Estimation and planning are crucial for successful software development projects, ensuring project readiness and preventing potential issues. Planning poker, an effective estimation method for agile teams, combines professional judgment, analogy, and disaggregation for fast, accurate estimates. The estimation technique Planning Poker is frequently employed in agile software development. When submitting estimates, Planning Poker only uses specific numbers on its cards, such as 0, 1, 2, 3, 5, 8, 13, 20, 40, and 100. This is inaccurately referred to in this work as a Fibonacci scale. Despite the frequent use of the Fibonacci scale in agile estimation, it is unknown how it influences the estimation process. Objectives: We conducted a study based on a software provider who estimates projects using a variety of estimation methods. Method: We used the planning poker technique for estimation. Findings: Using a Fibonacci scale as opposed to the conventional linear scale resulted in a median decrease in effort estimates. As the developer's proficiency increased, the disparity between the effort estimates shrank. Novelty: For the purpose of estimating the project of a software development company that is presently in operation, we have utilized the currently available estimation method.