Currently, we don't have an export that will expose this data to you in a straightforward way, but you can find this if you do some manual work.
You would begin by downloading the Subscriptions export for the month you are reconciling and set a Subscription status of All. Once downloaded, remove all subscriptions with a trial_starts_at date outside of the day you are looking at. Also, remove any subscriptions that do not have the trial_starts_at and trial_ends_at columns populated as these did not start with trials. You will want to compare the trial_ends_at date with the current_period_started_at column in the export to confirm that the trial ended and converted to a paid subscription.
I recommend going through all canceled subscriptions since those are still active and may appear to be converted since their expires_at dates are after the trial_ends_at dates. You may find that most never converted (if their payments failed), so make sure to remove those from the list.
Next, filter out the expired subscriptions (Status column) so you can review these, because some may have actually converted and then terminated immediately. To do this, remove all subscriptions that have matching trial_end_at and expires_at dates. Then, go through each one individually and check their activity history to see if they initially converted (paid after trial) and were then refunded and churned. These would be counted toward the Trial Performance total.
If you go through the process above and still cannot get the totals to match, make sure you are taking coupons, credits and gift cards into account. This dashboard will only include subscriptions that converted to paid subscriptions, which means that the invoice generated after the trial expired must be above $0. Discounts of any kind that bring down that total to $0 mean that the subscription will not be included in that metric.