You don't even need decimals. Nobody who uses celsius gives a shit about the decimals. It's -4 or it's -5 and even that distinction is irrelevant.

Unless you're doing some kind of scientific calculaton there's no need to think about decimals of celsius at all. Just like Fahrenheit users surely don't care whether it's 50 or 53 or whatever. It's around 50, that's all you need to know.