A company uses the percentage of completion method to account for a three year construction contract. Which of the following should be used in the calculation of the income recognized in the first year of the contract? (a) Progress billings. (b) Actual construction costs for year. (c) Collections on progress billings. (d) Estimated construction costs for year. 17. 18. A company started a long term construction project in 20X0. The following data relate to this project