Continuation on 'mapped' yields single result only

#include <QCoreApplication>
#include <numbers>
#include <cmath>
#include <QtConcurrentMap>

int main(int argc, char* argv[])
{
    QCoreApplication a(argc, argv);

    auto fCalculateArea = [](const double radius)
        {
            return std::pow(radius, 2.0) * std::numbers::pi;
        };
    auto fFormatArea = [](const double area)
        {
            return QString("%1 m²").arg(QString::number(area,'f'));
        };

    QList<double> vecInputs{2.0, 6.0, 9.0};
    auto future = QtConcurrent::mapped(vecInputs, fCalculateArea)
                      .then(fFormatArea);
    future.waitForFinished();
    qDebug() << "Number of inputs:" << vecInputs.size() <<
                "Number of results:" << future.resultCount();
}