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bn January 1,2018, ABC Co. granted 1,000 share options at an exercise price of P50 to each of its 30 key management personnel. They had to stay with the entity for 4 years. At grant date, the fair value of the share options was estimated at P30 and the entity estimated that the options would vest with 20 managers. This estimate didn't change in 2018. On January 1, 2019, the share price increase so that the entity modified the scheme by increasing the exercise price to P75. Find the following: a. salaries expense for the year 2018, 2019, 2020 and 2021