来自具有不同属性类型的对象的类型

Question

我想从我的状态对象创建一个类型，该类型具有键和字符串类型的值。我想创建一个具有相同键的类型并将值解析为数字或浮点型。这是我到目前为止所做的。

let state= {
    amountTotal: "",
    usedPointAmount: "",
    amountMinus: "",
    amountPayed: "",
}

type reduceType = {
    [key in keyof typeof state]: number;
};

let parseState: reduceType = () => {
    let reduced = (Object.keys(state) as Array<keyof typeof state>).reduce<
        reduceType
    >((prev, current) => {
        return {
            ...prev,
            [current]: parseFloat(state[current].replace(/\s/g, "")),
        };
    }, {});
    return reduced;
};

但是reduce函数的返回类型不再是reduceType吗？是该错误还是另外一个expected behavior。