Return Error on Method with If/Else Statements [duplicate]

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• Java: Error: variable might not have been initialized 2 answers

I have the following method in my code:

private static double mailTypeOne(double oz) {
    double total;
    if (oz <= 16) {
        total = 3.50;
    } else if (oz > 16 && oz <= 32) {
        total = 3.95;
    } else if (oz > 32) {
        total = 3.95 + (Math.ceil((oz - 32) / 16) * 1.20);
    }
    return total;
}

And the return statement causes a compile error:

the variable 'total' might not have been initialized

What's the issue?