public double getAverage() {
        if (null == movingAverage) { movingAverage = new MovingAverage(getAveragingPeriod()); }
        return movingAverage.getAverage();
    }
Returns the moving average over the number of values
defined by averagingPeriod.
@return the moving the average over the number of values defined by averagingPeriod
src/main/java/eu/hansolo/tilesfx/Tile.java