Build an Explore query using bar view that will return a count of events that is filtered to action that matches purchase and split it by region. This should start 2 weeks ago and end now.
Once your query returns pay attention to the values each bar represents. Because we used a split by (or group by for those of you familiar with SQL) we are taking the numeric result returned by measure 1 (count of events filtered to events with action that matches purchase) and showing it divided up among the values present under the field region.
Note: The numbers and result does not need to be an exact match as the data changes over time. The query construction is what is most important. See images below.
*Click to enlarge*