- - freqa-dec in [ ]ts asfreq(' 'how='start'out[ ] - - - - - - freqm in [ ]ts asfreq(' 'how='end'out[ ]- - freqb figure - period frequency conversion illustration quarterly period frequencies quarterly data is standard in accountingfinanceand other fields much quarterly data is reported relative to fiscal year endtypically the last calendar or business day of one of the months of the year as suchthe period has different meaning depending on fiscal year end pandas supports all possible quarterly frequencies as qjan through -decin [ ] pd period(' 'freq=' -jan'in [ ] out[ ]period(' '' -jan'in the case of fiscal year ending in january runs from november through januarywhich you can check by converting to daily frequency see figure - for an illustrationin [ ] asfreq(' ''start'out[ ]period(''' 'in [ ] asfreq(' ''end'out[ ]period(''' 'periods and period arithmetic www it-ebooks info