Creating a Token with 1000 supply, what decimals should i use

Hello, I am creating a token with limited supply of 1,000. What decimals am i expected to use for this?


Example in the code below, what do i need to change to reflect i want a total supply of just 1000?

uint8 private constant _decimals = 8;

uint256 public constant InitialSupply=  1000000000 * 10**_decimals;