I don't love the 'annualised' quarterly growth rates shown in this chart, it is more for demonstrative purposes.
You can select the cities you want displayed by clicking on the corresponding coloured dots. The 'stacked' option is of no use in this example (I will learn how to turn it off for future charts).
Thanks to Ramnath Vaidyanathan for his rapid reponses to questions about rCharts - http://rcharts.io/