Congress enacts a law imposing a 5% tax on the gross receipts of common carriers. The law does not define the term "gross receipts". Express Transport, Inc., a bus company plying the Manila-Baguio route, has time deposits with ABC Bank. In 2005, Express Transport earned P1 Million interest, after deducting the 20% final withholding tax from its time deposits with the bank. The BIR wants to collect a 5% gross receipts tax on the interest income of Express Transport without deducting the 20% final withholding tax. Is the BIR correct? Explain.