How to accurately get data between your customised periods specified

Hi everyone,

One thing that I am confused with regarding get_data_async, is that, depending on the datapoints I try and retrieve, I can't seem to get data within the scope of years that I specify. Say I have this for example:

 current_year = datetime.today().year
    start_year = current_year - 8
    async with semaphore:  # Controls the number of concurrent tasks
        global progress_counter
        try:
            # Retrieve data asynchronously for the given RIC
            response = await content.fundamental_and_reference.Definition(
                universe=[f'{ric}'],
                fields=specific_fields,
                parameters={"SDate": f"{start_year + 1}-01-01", "EDate": f"{current_year}-12-31", "Frq": "Y"}

For datapoints like EBIT and Total Cap, (assuming the start year is 2016 and the end year is 2024), I am getting data for only 2015 to 2022. And I have seen this inconsistency across different datapoints as well. Why is this happening, and what is the cause?

Thanks!