You can change the decimal settings for your CORE company at the global level from Settings > Display & Formatting > Number Formatting. You can change the number of digits after decimal for rate, units, and HR benefits. The rate is set to 2 places of decimal by default; charge amount is set to 2 places of decimal, and so on. However, you can change these defaults by specifying your preferred decimal value, say 3 or 4, and not have CORE round it off to 2 decimal places.
The only exception is Cost Rate in Expense Entries, where it always shows 4 digits after the decimal point. This is to accommodate the expense items that may have granular calculations, e.g., mileage. If the IRS mileage rate is $0.545, CORE rounds it off to $0.55 when the decimal is set to 2 places. Also, you cannot round off the invoice amount to 3 decimal places because that is not in accordance with the GAAP accounting rules. Check CORE Help for details.
Note: Percentages in CORE aren't designed to be rounded in any way. CORE calculates percentages to display only true values.