I fly COPA routes a bunch and often get ~1.3X PQP per USD paid. You can see the fare class of the ticket you might purchase on the COPA website by selecting the ticket you want (e.g., "Economy Classic") and then when you're at the next page clicking on the "Economy Classic" button link (which highlights as "Fare Rules" when you hover over it). This link button is to the left of the "View Details" and "Change Flight" button links. Once you click on the "Fare Rules", it will show you the fare codes of each segment. Usually I find that it's T for the really low fare tickets (which it says earns 25% PQP on the United website) but often I also get W, E, or L (50%). Occasionally for higher-priced Economy Classic it's V, U, S or O (75%). I usually try to select the ones that are 50-75% earning.