Historical Data Backfill Behavior

[kshillingstad]

When/why does the backfill trigger when downloading historical data?

openbb_terminal/stocks/comparison_analysis/yahoo_finance_model.py

if np.any(df_similar.isna()):
        nan_tickers = df_similar.columns[df_similar.isna().sum() >= 1].to_list()
        console.print(
            f"NaN values found in: {', '.join(nan_tickers)}.  Backfilling data"
        )
        df_similar = df_similar.fillna(method="bfill")

    df_similar = df_similar.dropna(axis=1, how="all")

    if end_date:
        df_similar = df_similar[df_similar.index <= end_date]
    return df_similar

Is there a way to avoid backfilling missing data/retry or is this to fill in gaps in the data that is available on yahoo finance?

Thanks!

[kshillingstad]

After further research it looks like this is in place due to yahoo finance being unreliable and occasionally having null values for stocks.