I read through the API change topic http://www.tt-forums.net/viewtopic.php?f=65&t=44249 and noticed someone asked for a way to get to the quarterly company information. Since I also need this information for the next version of my AI I decided to implement these features. The given patch adds the following functions:
Money GetQuarterlyIncome(CompanyID company, uint32 quarter);
Money GetQuarterlyExpenses(CompanyID company, uint32 quarter);
int32 GetQuarterlyCargoDelivered(CompanyID company, uint32 quarter);
int32 GetQuarterlyPerformanceRating(CompanyID company, uint32 quarter);
Money GetQuarterlyCompanyValue(CompanyID company, uint32 quarter);
if quarter is equal to 0 (AICompany::CURRENT_QUARTER) it will display the current value (except for the Performance Rating, because it is calculated at the end of every quarter).
I have not updated the regression test, but I'll do so once people are happy with the code provided. Note that int32 GetQuarterlyPerformanceRating(CompanyID company, uint32 quarter); makes AICompany::GetPerformanceRating(CompanyID company) redundant - I haven't removed it but if this patch gets accepted I suspect the latter will eventually be phased out.
Hope it gets included

Bram