The file P16_27.xlsx contains quarterly sales of Johnson & Johnson. A time series plot of this series indicates a clear upward trend. Use moving averages to forecast this series, experimenting with...

The file P16_27.xlsx contains quarterly sales of Johnson & Johnson. A time series plot of this series indicates a clear upward trend. Use moving averages to forecast this series, experimenting with the span. What do you conclude about the effectiveness of using moving averages on an upward-trending time series?