These are simulated data. `htseg1`

has three levels with a total of 8
series each of length 10. `htseg2`

has four levels with a total of 17
series each of length 16.

Objects of class `hts`

.

## References

R. J. Hyndman, R. A. Ahmed, G. Athanasopoulos and H.L. Shang
(2011) Optimal combination forecasts for hierarchical time series.
*Computational Statistics and Data Analysis*, **55**(9), 2579--2589.
https://robjhyndman.com/publications/hierarchical/

## Examples

plot(htseg1)