What is the correct approach to apply the XIRR formula in my own investment? (opens in new tab)

I have an investment bank account. I need to deposit cash now and then into the account so that there is enough cash to BUY/SELL stocks. In addition to tradings, there are also dividend payments to the same bank account. Question: Should the IRR be calculated on base of the bank account transactions or merely on base of the portfolio, i.e. only the BUY/SELL are taken into consideration?