Let's be clear. By default, Access shows you what is in the field. If you open the table and look at that value in Datasheet view, is it 2.8 or 3 ?
Rounding occurs when the data type of the field in the table doesn't support the precision you request. ANY of the integer types will do this, including LONG and INTEGER (a.k.a. WORD) data types. If the data type in the table is not SINGLE, DOUBLE, CURRENCY, or DECIMAL then you cannot have decimal points anyway. However, one can find general advice to avoid using DECIMAL anyway because of its issues in data handling.
Use Double rather than Decimal for Microsoft Access number field sizes
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