Monthly foreign exchange rates: US dollar and UK pound against the Australia
audusd contains USD/AUD and
audukp contains UKP/AUD.
multiple time series
Hyndman, R.J., Koehler, A.B., Ord, J.K., and Snyder, R.D., (2008) Forecasting with exponential smoothing: the state space approach, Springer.
plot(xrates,main="Foreign exchange rates",xlab="Year")