Merchant Dashboard - Google Spend chart client locale vs budget currency

The campaign (in this case for merchant Martian tours) uses a budget of Yen.
In the Reseller UI, the Google Spend chart displays JP¥ in both the Y-axis and in the tool-tip for amount spent.
In the Merchant Dashboard, the currency displayed in the Google Spend Y-axis and the tooltip changes depending on browser language settings, not by choosing a language in the log in page (i.e. currency displayed as US$ or GB£)