def purchase_intention(people_who_declared_interest, total_people):
    """Returns the purchase intention rate for a product.

    This can be used for cart-to-detail, buy-to-detail, and similar calculations.

    Args:
        people_who_declared_interest (int): Number of people who declared interest in a product.
        total_people (int): Total number of people.

    Returns:
        Percentage of people who were interested in a product.
    """

    return (people_who_declared_interest / total_people) * 100