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An entry in these fields may be required only for corporations with a year end before 2019. TurboTax business Inc will automatically populate these fields in the Small Business Deduction (SBD) section based on the entered tax year; manual entries in this section are not required. Depending on the tax year of the corporation different percentages are used in the SBD section calculations: these changed as a result of Canada Revenue Agency changes. The rates changed from 17.5% to19% and depend on the number of days the tax year fell into each of those listed time periods.
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