For all flights with AA flight numbers (either AA prime flights or AA codeshares operated by another airline), it's the pro-rated base fare plus the YQ/YR associated with the flight. To calculate the pro-rated fare, add up the flight distance of each flight, then for each AA-coded segment, divide the flight distance of that segment by the total flight distance, then multiply this number by the base fare. Determining which YQ/YR to allocate to which segments is harder; my spreadsheet allocates it exactly the same as it does the base fare (pro-rated by percent of total flight distance), and it works out fairly close to what AA awards, but perhaps [MENTION=77686]ernestnywang[/MENTION] can suggest a better way?

EDIT TO ADD: On occasion, AA credits RTW AA flights using flight distance, which results in far more miles and LPs than using fare, but when this happens it is a glitch and sometimes AA goes back and corrects it later. A few years ago it was possible to have an AAdvantage Customer Service agent manually adjust RTW segments to calculate using distance, but that ability has been removed from the agents' capabilities.