Calculating Margin Borrow Amount

This is NOT a question about the endpoint GET /sapi/v1/margin/maxBorrowable to get max borrow amount, as someone has suggested as an answer and closed my topic. maxBorrowable is pretty straightforward, but is not related to my question. Question is about something else. Please, read carefully.

Trying to figure out how does Binance calculate the Margin Borrow Amount.
Following is a real example:
{‘clientOrderId’: ‘xxxxxxx’,
‘cummulativeQuoteQty’: ‘87.8704292’,
‘executedQty’: ‘0.00164’,
‘fills’: [{‘commission’: ‘0.08787043’,
‘commissionAsset’: ‘USDT’,
‘price’: ‘53579.53’,
‘qty’: ‘0.00164’}],
‘isIsolated’: False,
‘marginBuyBorrowAmount’: ‘0.00163204’,
‘marginBuyBorrowAsset’: ‘BTC’,
‘orderId’: xxxxxxx,
‘origQty’: ‘0.00164’,
‘price’: ‘0’,
‘side’: ‘SELL’,
‘status’: ‘FILLED’,
‘symbol’: ‘BTCUSDT’,
‘timeInForce’: ‘GTC’,
‘transactTime’: 1633623180921,
‘type’: ‘MARKET’})

How does Binance calculate the marginBuyBorrowAmount?
Anyone can give a clear idea?
Much appreciated…

you can call this endpoint GET /sapi/v1/margin/maxBorrowable to get max borrow amount.