We cannot do this as a default statistic because it does not make sense for users who play multiple currencies. We can only add USD and EUR by converting.
However, if you're only playing in one currency, you can create a custom stat very easily that will display as you would like.
Click Configure --> Statistics. In the Cash Players Stats page click on Game Currency Won and click the Duplicate button. Rename the stat to whatever you would like (but it does need to be slightly different). In the Summary Type drop down choose "Same as Format" and save your stat. Configure your report (via right click --> Configure Report) to show your new stat and you're all set.
