Incorrect month for financial reports being retrieved

I'm pulling Financial reports using the App Store API. It's sending me the incorrect month's data. For example, when I request financial data for December 2018, the API returns financial data for September 2018. I thought maybe it's returning financial data for whatever was paid out in December 2018, but that's not the case either as I was paid out for September 2018 sales in November 2018.


Is anyone else having this problem?


Here's an example of my request made via cURL:


curl -v -g -H "Authorization: Bearer <signed JSON token>" "https://api.appstoreconnect.apple.com/v1/financeReports?filter[regionCode]=ZZ&filter[reportDate]=2018-12&filter[reportType]=FINANCIAL&filter[vendorNumber]=<vendor ID>"


It returns gzipped data that, when deflated, is tab-delimited file of all sales from September 2018. When I increase the date, it keeps returning data offset by 3 months. In fact, it's currently March 3, 2019 today but if request data for 2019-04 then I get sales data for January 2019.

I figured it out. Apple doesn't want the actual year and month from the Gregorian calendar, but rather the year and month of their own fiscal accounting calendar. So 01 is October, 02 is November, and so on.

Incorrect month for financial reports being retrieved
 
 
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