Showing converted currency value in record view

Hi

On our opportunities page, for one field, we have the base currency and a non base currency. For some fields, it shows the opportunity's currency in a grey box and the value converted into the system's base currency.

However I cannot see in the studio how to enable this conversion; I have added a new field called Test Value as a currency type, but it does not show the converted field.

<div class="record-label" data-name="amount">
    Revenue
</div>
<span class="normal index" data-fieldname="amount" data-index="">
    <span sfuuid="41" class="detail" tabindex="-1">
        <div class="currency-field">
            <label class="original">€1,000.00</label>
            <div class="converted">£847.46</div>
        </div>
    </span>
</span>

The closest thing I can find is in

/clients/base/fields/currency/details.hbs

<div class="currency-field"{{#if dir}} dir="{{dir}}"{{/if}}>
{{#if transactionValue}}
    <label class="original">{{transactionValue}}</label><div class="converted">{{value}}</div>
{{else}}
    {{value}}
{{/if}}
</div>

which contains the template to show this conversion, but I don't know how to enable this for other fields.